615

615 = 3 x 5 x 41. It is the product of three distinct Sophie Germain primes (A157346).

615 is a hypotenuse for which there exist four distinct integer triangles (A084648).

615 is the sum of seven positive fifth powers (A003352): 615 = 3⁵ + 3⁵ + 2⁵ + 2⁵ + 2⁵ + 2⁵ + 1⁵.

The sum of the even digits of 615 equals the sum of the odd digits of 615 (A036301).

Source: On-Line Encyclopedia of Integer Sequences