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