117

This number is a composite.

+ 1172 ± 2 are primes. [Russo]

+ 117 can be written as the difference of prime squares (112 - 22) or prime cubes (53 - 23). [Sladcik]

+ 117 = (1!2 + 1!2 + 7!2) + (π(1)!2 + π(1)!2 + π(7)!2). Note that 117 is the only number with this property. [Firoozbakht]

Printed from the PrimePages <t5k.org> © G. L. Honaker and Chris K. Caldwell