190633

This number is a prime.

+ 2^^n-7 = 2^(2^(2^...(2^2)..))-7 is divisible by 190633 for all sufficiently large n. 190633 is the only prime (besides 3) less than a million for which this is true. [Hartley]

Printed from the PrimePages <primes.utm.edu> © G. L. Honaker and Chris K. Caldwell