715 = 5 x 11 x 13.
715 is the tenth pentatope number. It is also a pentagonal number (A000326), a hendecagonal number (A051682), and a hexagonal pyramidal number (A002412).
715 is 222111 in base 3, 23023 in base 4, and 1313 in base 8.
715 is the number of intersections of diagonals in the interior of a regular 13-gon (A006561).
715 is the smallest positive number that can be written as a sum of distinct Fibonacci numbers in 26 ways.
Source: Number Gossip