700 = 22 x 52 x 7.
700 is the sum of four consecutive primes: 700 = 167 + 173 + 179 + 181.
700 is a number that cannot be written as a sum of three squares.
700 is 221221 in base 3 and 2020 in base 7.
700 is the number of n-bead necklaces with four colors, for n = 7.
Source: Wikipedia