196

196 = 2² x 7².

196 is the smallest square that contains a multidigit prime number as a substring.

196 = 14² is a perfect square.

196 is the difference of two square numbers: 196 = 50² - 48².

The consecutive squares 13² = 169 and 14² = 196 use the same digits; 31² = 961 also uses the same digits.

196 has a unique representation as a sum of three squares: 196 = 4² + 6² + 12².

196 is a pentagonal pyramidal number and a heptagonal pyramidal number.

It is conjectured that 196 is the lowest Lychrel number. It is the lowest number not known to produce a palindrome by repeated reversal and addition. The algorithm has been tested to more than 246 million digits without finding a palindrome, but no one has ever proved that it will never produce one.

The Mercedes-Benz W196 was an entry in the 1954 and 1955 Formula One car racing series, winning 9 of 12 races.

Source: Number Gossip

482

482 = 2 x 241.

482 has a representation as a sum of two squares: 482 = 11² + 19².

482 is 222 in base 15. It is 585 in base 9.

482 is a number whose square (232,324) and cube (111,980,168) use different digits.

482 Music is an independent record label featuring international jazz.

Source: What's Special About This Number?

981

981 = 3² x 109.

981 has a representation as a sum of two squares: 981 = 9² + 30².

327 + 654 = 981 uses each of the digits 1-9 once.

981 and 981² = 962,361 have the same initial digit and final digit.

Turkish Airlines Flight 981 was a McDonnell Douglas DC-10 that crashed in France in 1974, killing all 346 people on board.

Source: Numeropedia

186

186 = 2 x 3 x 31.

186 is the maximum number of regions into which 9 spheres divide space.

7 x 5 x 3 x 2 - 4 x 3 x 2 x 1 = 186.

186 x 39 = 7254 uses each of the nine digits 1-9 once.

186 is 1221 in base 5 and 272 in base 8.

186 is the number of odd days in a year that is not a leap year.

Source: Number Gossip

594

594 = 2 x 3³ x 11.

594 is 1001010010 in base 2 (binary). It is 4334 in base 5 and 1122 in base 8.

594 is the smallest number that has 10 representations as a sum of three positive squares: 594 = 1² + 8² + 23² = 3² + 3² + 24² = 3² + 12² + 21² = 4² + 7² + 23² = 4² + 17² + 17² = 5² + 13² + 20² = 7² + 16² + 17² = 8² + 13² + 19² = 12² + 15² + 15² = 13² + 13² + 16².

594 = 1⁵ + 2⁹ + 3⁴.

594 is the sum of 10 consecutive primes: 594 = 41 + 43 + 47 + 53 + 59 + 61 + 67 + 71 + 73 + 79.

USS Permit (SSN-594) was a nuclear submarine that was launched in 1961 and decommissioned in 1991.

Source: What's Special About This Number?

976

976 = 2⁴ x 61.

976 is a decagonal number. It is also a centered triangular number.

976 has a square formed by inserting a block of digits inside the original number: 976² = 952,576.

976 has a representation as a sum of two squares: 976 = 20² + 24².

976 is a divisor of 11⁴ - 1.

976-EVIL is a 1989 horror film directed by Robert Englund.

Source: What's Special About This Number?

680

680 = 2³ x 5 x 17.

680 is the 15th tetrahedral number. It is the smallest tetrahedral number that is also the sum of two tetrahedral numbers: 680 = 560 + 120.

680 has two representations as a sum of two squares: 680 = 2² + 26² = 14² + 22².

680 is 404 in base 13.

680 can be written as the sum of distinct odd powers of two: 680 = 2³ + 2⁵ + 2⁷ + 2⁹.

WCBM AM 680 is a talk radio station in Baltimore.

Source: Number Gossip

458

458 = 2 x 229.

458 has a representation as a sum of two squares: 458 = 13² + 17².

458 is a number that does not have any digits in common with its cube: 458³ = 96,071,912.

458² contains exactly six different digits: 458² = 209,764.

The Ferrari 458 Italia is a sports car that was introduced in 2009.

Source: What's Special About This Number?

156

156 = 2² x 3 x 13. It is a pronic number because it is the product of two consecutive numbers: 156 = 12 x 13.

156 is 1111 in base 5.

156 is a dodecagonal number.

156 is the number of graphs with six vertices.

A clock will strike 156 times in the course of a day.

Source: Number Gossip

452

452 = 2² x 113.

452 has a representation as a sum of two squares: 452 = 14² + 16².

452 is a divisor of 15⁴ - 1.

452 is 381 in base 11 and 318 in base 12. It is 202 in base 15.

452 is the sum of seven nonzero 4th powers.

The Petronas Towers in Kuala Lumpur, Malaysia, are 452 meters tall (including antenna spires).

Source: The Positive Integers

857

857 is a prime number.

857 has a representation as a sum of two squares: 857 = 4² + 29².

857 and 859 form a twin prime pair.

857 is the hypotenuse of a primitive Pythagorean triple: 857² = 232² + 825².

142,857 x 5 = 714,285 = 857² - 142², where 857,142 = 142,857 x 6.

857 is 1011202 in base 3. It is 272 in base 19.

857 is the sum of three consecutive primes: 857 = 281 + 283 + 293.

Glasenappia 857 is an asteroid discovered in 1916.

Source: Wikipedia

339

339 = 3 x 113.

339 is the number of ways to divide 5 black and 5 white beads into piles.

339³ = 38,958,219 = (389 - 58 - 2 + 1 + 9)³.

339 is 2324 in base 5 and 1323 in base 6. It is 523 in base 8.

339 is the sum of the squares of three consecutive primes: 339 = 7² + 11² + 13².

The Gibson ES-339 is a custom hand-crafted electric guitar.

Source: What's Special About This Number?

143

143 = 11 x 13.

143 is the smallest brilliant number whose reversal, 341, is a different brilliant number.

143 is an aspiring number.

The last 143 digits of 143¹⁴³ form a prime number.

143 is the number of three-digit primes.

Every positive integer is the sum of at most 143 seventh powers.

143² is a divisor of 143143.

143 is the sum of three consecutive primes and the sum of seven consecutive primes: 143 = 43 + 47 + 53 = 11 + 13 + 17 + 19 + 23 + 29 + 31.

Vickers Type 143 was a British single-seat biplane designed and built in 1929.

Source: Number Gossip

247

247 = 13 x 19. Its digits sum to the smallest prime factor: 2 + 4 + 7 = 13.

247 is a pentagonal number.

247 is the smallest possible difference between two integers that together contain each digit exactly once: 247 = 50,123 - 49876.

247² is one of six square numbers that use the same digits: 247² = 61,009; 130² = 16.900; 140² = 19,600; 310² = 96,100; 103² = 10,609; and 301² = 90,601.

247 Eukrate is a large, dark asteroid discovered in 1885.

Source: Prime Curios!

551

551 = 19 x 29.

551 is the sum of three consecutive primes: 551 = 179 + 181 + 191.

551 is a centered decagonal number.

551 is the number of trees with 12 vertices.

551 is 202102 in base 3 and 20213 in base 4.

551 is a divisor of 30³ - 1.

551 Ortrud is an asteroid discovered in 1904.

Source: What's Special About This Number?

6200

6200 = 2³ x 5² x 31.

6200 is 22111122 in base 3 and 8448 in base 9. It is 14070 in base 8.

6200 is a harmonic divisor number.

6200 is a multiple of 8 with a digit sum of 8.

6200 is a divisor of 99⁶ - 1.

The GeForce 6200 from Nvidia is a graphics processing unit introduced in 2004.

Source: What's Special About This Number?

621

621 = 3³ x 23.

621 is the number of ways to 9-color a tetrahedron.

621 is 4441 in base 5. It is 515 in base 11.

621² = 385,641 contains exactly six different digits.

621 is the sum of two distinct positive pentatope numbers: 621 = 126 + 495.

The USS Haddock (SSN-621) was a nuclear-powered submarine launched in 1966 and decommissioned in 1993.

Source: What's Special About This Number?

410

410 = 2 x 5 x 41.

410 has two representations as a sum of two squares: 410 = 7² + 19² = 11² + 17². 410 is the smallest number that can be represented as the sum of the squares of distinct primes in two different ways.

410 is 120012 in base 3, 12122 in base 4, and 1124 in base 7. It is 505 in base 9 and 343 in base 11.

410 is the sum of six consecutive primes: 410 = 57 + 61 + 67 + 71 + 73 + 79.

410 is the telephone area code for the Baltimore area of the state of Maryland.

Source: Prime Curios!

1099

1099 = 7 x 157.

1099 is 777 in base 12.

1099 = 1 + 0 + 999 + 99.

1099 and 1099² = 1,207,801 have the same digit sum: 1 + 0 + 9 + 9 = 1 + 2 + 0 + 7 + 8 + 0 + 1 = 19.

1099 is the sum of seven consecutive primes: 1099 = 139 + 149 + 151 + 157 + 163 + 167 + 173.

In the United States the 1099 IRS tax form shows how much an independent contractor made from a certain business.

Source: What's Special About This Number?

222

222 = 2 x 3 x 37.

222 is the number of integer partitions of 28 into distinct parts.

222 is the smallest number with three prime digits.

The number 222² + 222²² + 222²²² + 1 is a prime.

222 is 1010 in base 6. It is 141 in base 13.

Room 222 was a TV show that aired from 1969 to 1974.

Source: Number Gossip

8184

8184 = 2³ x 3 x 11 x 31.

8184 is a divisor of 97⁵ - 1.

8184 has the representation 2¹³ - 8.

8184 is 1333320 in base 4 and 12203 in base 9. The set of base 4 digits of 8184 equals the set of base 9 digits: {0, 1, 2, 3}. 8184 contains exactly the same digits (with the correct multiplicity) in three different smaller bases.

The product of the digits of 8184 is 8 x 1 x 8 x 4 = 256 = 4⁴, where 4 is the number of digits.

8184² = 66,977,856 contains no digit less than 5.

Lego set 8184 is an RC Racer.

Source: What's Special About This Number?

807

807 = 3 x 269.

807!/708! - 1 is a prime number.

807 and 807² = 651,249 combined use different digits.

807 is the sum of two pentagonal numbers in exactly two ways: 807 = 715 + 92 = 477 + 330.

807 is the sum of 13 positive fifth powers.

Telephone area code 807 covers the northwestern portion of the province of Ontario.

Source: Prime Curios!

405

405 = 3⁴ x 5.

405 has a representation as a sum of two squares: 405 = 9² + 18².

405 is a pentagonal pyramidal number.

405 is 120000 in base 3 and 12111 in base 4. It is 500 in base 9.

405 is a tridecagonal number.

405 is the telephone area code for central Oklahoma.

Source: What's Special About This Number?

502

502 = 2 x 251.

502 is a divisor of 5²⁵ - 1.

502 is an Eulerian number.

502 and its reversal (205) are both semiprimes (the product of two primes).

502 is a number such that the sum of its base 2 digits (1 + 1 + 1 + 1 + 1 + 0 + 1 + 1 + 0 = 7) is equal to the sum of its base 10 digits (5 + 0 + 2 = 7).

Telephone area code 502 serves Louisville, Kentucky, and the surrounding area.

Source: On-Line Encyclopedia of Integer Sequences

1318

1318 = 2 x 659.

1318 is a semiprime with a prime sum of factors: 2 + 659 = 661, a prime. 1318 is a semiprime that is 1 less than a prime, 1319.

1318 is a divisor of 55⁷ - 1.

1318 is 414 in base 18.

1318 is the rectilinear crossing number of a complete graph of 19 nodes.

IC 1318 is the Gamma Cygni nebula.

Source: On-Line Encyclopedia of Integer Sequences

367

367 is a prime number.

367 is a prime number whose digits are distinct and, expressed in English, are in reverse alphabetical order.

367 is the sum of two consecutive composite numbers: 367 = 183 + 184.

367 is the largest number whose square has strictly increasing digits: 367² = 134,689.

367 is 11233 in base 4. It is 557 in base 8 and 447 in base 9. It is 267 in base 12, 197 in base 15, and 127 in base 18.

The Pythagorean Proposition, by early 20th-century professor Elisha Scott Loomis, is a collection of 367 proofs of the Pythagorean theorem.

Source: Number Gossip

592

592 = 2⁴ x 37.

592 has a representation as a sum of two squares: 592 = 4² + 24².

592 is 2424 in base 6. It is 727 in base 9 and 414 in base 12. It is 250 in base 16.

592 is a Moran number: 592 divided by the sum of its digits (5 + 9 + 2) = 16) is a prime number (37).

Permuting the digits of 592 produces a square: 529 = 23².

Camelback 592 is a locomotive in the collection of the Baltimore & Ohio Railroad Museum.

Source: On-Line Encyclopedia of Integer Sequences

1317

1317 = 3 x 439.

1317 is palindromic in base 2 (binary): 1010001000101. It is 1210210 in base 3.

1317 is the concatenation of the sixth and seventh primes. It is also the concatenation of the seventh Fibonacci number and the seventh prime.

131771317 and 713177 are both primes.

1317 is a semiprime for which the product of its digits is also a semiprime: 1 x 3 x 1 x 7 = 21 = 3 x 7.

NGC 1317 is a galaxy with a starburst ring.

Source: On-Line Encyclopedia of Integer Sequences

3642

3642 = 2 x 3 x 607.

3642 is 320322 in base 4 and 7072 in base 8.

3642 is the number of labeled topologies with 5 points.

3642 and 3642² use only the digits 1, 2, 3, 4, and 6. The internal digits of the squared number include only the digits of the number.

36423641 and 36423643 are a pair of twin primes.

3642 is one of the 36 Class steam locomotives operated by the New South Wales Government Railways.

Source: On-Line Encyclopedia of Integer Sequences

311

311 is a prime number.

311 and 313 form a twin prime pair.

311 is the 11th three-digit prime for which the sum of the squares of its digits is also a prime: 3² + 1² + 1² = 11, a prime.

311 is the smallest number expressible as the sum of consecutive primes in four ways: 311 = 101 + 103 + 107 = 53 + 59 + 61 + 67 + 71 = 31 + 37 + 41 + 43 + 47 + 53 + 59 = 11 + 13 + 17 + 19 + 23 + 29 + 31 + 37 + 41 + 43 + 47.

311 is a rock/reggae band.

Source: Prime Curios!

1535

1535 = 5 x 307.

1535 is 113333 in base 4, 2777 in base 8, and 555 in base 17.

1535 is a Thabit (or 321) number, having the form 3 x 2ⁿ - 1 for n = 9.

The sum of the digits of 1535² (2,356,225) and the product of its digits are both squares: 2 + 3 + 5 + 6 + 2 + 2 + 5 = 25 = 5² and 2 x 3 x 5 x 6 x 2 x 2 x 5 = 3600 = 60².

NGC 1535 is a nebula in the constellation Eridanus.

Source: On-Line Encyclopedia of Integer Sequences

153

153 = 3² x 17.

153 is the 17th triangular number. It is also a hexagonal number.

153 = 1! + 2! + 3! + 4! + 5!

153 is palindromic in base 2 (binary): 10011001. It is 2121 in base 4 and 99 in base 16.

153 is the smallest number greater than 1 such that the sum of the cubes of its digits equals itself: 153 = 1³ + 5³ + 3³.

153 has a representation as a sum of two squares: 153 = 3² + 12².

In the Bible, Simon Peter is said to have caught 153 fish (John 21:11).

Source: Number Gossip

1414

1414 = 2 x 7 x 101.

1414 is a divisor of 95¹⁵ - 1.

1414 is the smallest number whose square contains three consecutive nines: 1414² = 1,999,396.

1414³ = 2,827,145,944 = (-28 + 27 + 1459 - 44)³.

1414 is 4060 in base 7 and 644 in base 15.

Studio 1414 is the second largest sound stage in Minnesota.

Source: What's Special About This Number?

1239

1239 = 3 x 7 x 59.

1239 is a value of n for which n⁸, n⁹, n¹⁰, and n¹¹ have the same digit sum (135).

1239 is the average of three successive primes (1231, 1237, 1249).

The sum of the squares of the factors of 1239 is a prime number: 3² + 7² + 59² = 3539, a prime.

1239 is the composite number displayed at the start of the music video "Prime Composition" by Daniel Jones.

Source: Prime Curios!

675

675 = 3³ x 5².

675 is the smallest order for which there are 17 groups.

675² = 455,625 = (45 + 5 + 625)².

675 is 300 in base 15. It is 10200 in base 5 and 120 in base 25.

Triumph manufactures the Daytona 675 sports motorcycle.

Source: What's Special About This Number?

378

378 = 2 x 3³ x 7.

378 is the 27th triangular number. It is also a hexagonal number and the smallest Smith triangular number.

378 is the smallest three-digit number in which the sum of the digits is equal to the sum of the prime factors: 3 + 7 + 8 = 2 + 3 + 3 + 3 + 7 = 18.

378 is a cake number.

378 Holmia is an asteroid discovered in 1893.

Source: Number Gossip

1184

1184 = 2⁵ x 37.

1184 has a representation as a sum of two squares: 1184 = 20² + 28².

1184 is one of a pair of amicable numbers. This is the first pair greater than 1000: 1184 and 1210.

1184 is 1121212 in base 3, 14214 in base 5, 5252 in base 6, 3311 in base 7, 1555 in base 9, and 828 in base 12. It is 987 in base 11.

NGC 1184 is a galaxy in the constellation Cepheus.

Source: Number Gossip

964

964 = 2² x 241.

964 is the number of 3 x 3 sliding puzzle positions that require exactly 12 moves to solve starting with the hole in the center.

964 has a representation as a sum of two squares: 964 = 8² + 30².

964 has the representation 964 = 2¹⁰ - 60.

964 is a divisor of 15⁶ - 1.

964 is 444 in base 15.

The Porsche 964 was the company's internal name for a version of the Porsche 911 manufactured between 1989 and 1994.

Source: What's Special About This Number?

558

558 = 2 x 3² x 31.

558 is a divisor of 25³ - 1. It is also a divisor of the sum of the largest prime factors of the first 558 positive integers.

558 in base 3 and base 4 starts off with the same three digits: 202200 and 20232.

The sum of the digits of 558 is six times the number digits: 5 + 5 + 8 = 18 = 6 x 3. 558 and 558² (= 311,364) have the same digit sum.

558 is the sum of no fewer than 17 fourth powers.

558 is in the title of an episode of Star Trek: Deep Space Nine: "The Siege of AR-558".

Source: Prime Curios!

240

240 = 2⁴ x 3 x 5.

240 is 11110000 in base 2 (binary).

240 is the number of equivalent hyperspheres in 8 dimensions that can touch an equivalent hypersphere without any intersections (kissing number).

240 is the smallest number with 20 divisors.

240 is a divisor of 31² - 1.

240 is a number that cannot be written as a sum of three squares.

240 is the number of distinct solutions of the Soma cube puzzle.

Source: Number Gossip

959

959 = 7 x 137.

959 is the first odd number that is not the sum of a prime and a power of two.

959 is a Carol number.

959² = 919,681 = (-9 + 1 + 968 - 1)².

959 is a divisor of 41⁸ - 1.

959 is a number that cannot be written as a sum of three squares.

The Porsche 959 was a sports car manufactured from 1986 t0 1989.

Source: Prime Curios!

890

890 = 2 x 5 x 89.

890 has two representations as a sum of two squares: 890 = 7² + 29² = 19² + 23².

890 is a divisor of 37⁸ - 1.

890 is 1188 in base 9.

890 is the sum of four consecutive primes: 890 = 211 + 223 + 227 + 229.

WLS 890 AM is a radio station in Chicago.

Source: Wikipedia

746

746 = 2 x 373.

746 has a representation as a sum of two squares: 746 = 11² + 25².

746 = 1⁷ + 2⁴ + 3⁶.

746 x 8 x 92 x 531 = 291,548,736. Both sides of the equation use each of the digits from 1 to 9 once.

746 is the sum of two nonzero pentagonal pyramidal numbers: 746 = 550 + 196.

A horsepower is a unit of power equal to about 746 watts.

Source: What's Special About This Number?

633

633 = 3 x 211.

633 is 1001111001 in base 2 (binary). It is 333 in base 14.

633 has the representation 633 = 3⁶ - 96.

633 is a divisor of 55⁵ - 1.

633 is the smallest number n whose fifth root has a decimal part that begins with the digits of n: 3.633128. . .

633³ = 253,636,137 = (2 - 5 + 3 + 636 + 1 + 3 - 7)³.

633 Squadron was a 1964 British film that depicted the exploits of a fictional World War II fighter-bomber squadron.

Source: What's Special About This Number?

327

327 = 3 x 109. The digits of 327 are themselves all primes.

327 is largest number n such that n, 2n, and 3n contain every digit from 1 to 9 exactly once: 327, 654, 981. In other words, the sum 327 + 654 = 981 contains each of the digits from 1 to 9 once.

327 is the number of 5s among the digits of all four-digit primes.

327 is a divisor of 76⁴ - 1.

327 is a number that cannot be written as a sum of three squares. It is the sum of four but no fewer squares.

The BMW 327 was a touring car produced between 1937 and 1941.

Source: What's Special About This Number?

440

440 = 2³ x 5 x 11.

440 is the sum of the first 17 primes (2 to 59).

440 is divisible by the sum of its prime factors: 2 + 2 + 2 + 5 + 11 = 22.

440 is the number of permutations of 12 items that fix nine elements.

440 and 441 are two consecutive numbers, each divisible by a square.

440 is the number of yards in the quarter-mile race in track-and-field competitions.

Source: Prime Curios!

606

606 = 2 x 3 x 101.

606 is both a 11-gonal (hendecagonal) number and a centered 11-gonal (hendecagonal) number.

606 is 4411 in base 5.

606 is the sum of six consecutive primes: 606 = 89 + 97 + 101 + 103 + 107 + 109.

606 is the telephone area code the covers the eastern part of the state of Kentucky.

Source: What's Special About This Number?

303

303 = 3 x 101.

303 is the number of bipartite graphs on eight nodes (vertices).

303³ = 27,818,127, which is a concatenation of the cubes 1, 8, and 27.

303 is a divisor of 101² - 1.

303 is a number that cannot be written as a sum of three squares.

In the Gregorian calendar, 303 is the number of years that are not leap years in a period of 400 years.

Source: What's Special About This Number?

521

521 is a prime number.

521 has a representation as a sum of two squares: 521 = 11² + 20².

521 is the 13th Lucas number.

521 and 523 for a twin prime pair.

521 is the hypotenuse of a primitive Pythagorean triple: 521² = 279² + 440².

521 has the representation 521 = 2⁹ + 9.

521 is the exponent of the Mersenne prime 2⁵²¹ - 1.

521 is the smallest prime whose reversal is a cube: 125 = 5³.

Galaxy cluster Abell 521 is located about 2.9 billion light-years from Earth.

Source: Prime Curios!

174

174 = 2 x 3 x 29.

174 is a divisor of 59² - 1.

174 is the number of twin primes among the first thousand primes.

174 = 7² + 5³.

174 is the smallest number that can be written as the sum of four positive distinct squares in six ways.

In 1978, Landon Noll and Laura Nickel used a CDC Cyber 174 to prove that the Mersenne number M₂₁₇₀₁ is a prime number.

Source: Prime Curios!