66 = 2 x 3 x 11.
66 is the 11th triangular number, the sum of the integers from 1 to 11.
66 is the smallest palindromic composite number n such that n2 + 1 is prime: 662 + 1 = 4357, a prime.
66 is the smallest number that can be expressed as a sum of two two-digit primes, each ending with the digit 3, in two different ways: 66 = 13 + 53 = 23 + 43.
U.S. Route 66 (also known as the Will Rogers Highway) ran from Chicago to Los Angeles and was the title of a weekly TV series (1960-1964).
Source: Prime Curios!
66 is the 11th triangular number, the sum of the integers from 1 to 11.
66 is the smallest palindromic composite number n such that n2 + 1 is prime: 662 + 1 = 4357, a prime.
66 is the smallest number that can be expressed as a sum of two two-digit primes, each ending with the digit 3, in two different ways: 66 = 13 + 53 = 23 + 43.
U.S. Route 66 (also known as the Will Rogers Highway) ran from Chicago to Los Angeles and was the title of a weekly TV series (1960-1964).
Source: Prime Curios!
