7740 = 2 x 2 x 3 x 3 x 5 x 43.
7740 is a pentagonal number (A049452). It is a pentagonal number that is not the difference of two larger pentagonal numbers (A136113), but it is the sum of two other positive pentagonal numbers (A136117).
7740 is 55500 in base 6 (A097252).
7740 is the number of primes less than 13! (A133228).
7740 is the sum of the interior angles of a 45-sided polygon in degrees (A066164).
7740 divides 496 - 1.
Source: Number Gossip