47

This number is a prime.

Just showing those entries submitted by 'Ballinger': (Click here to show all)

© Disney/Pixar

47 * 2⁵⁸³ + 1, 47 * 2¹⁴⁸³ + 1 and 47 * 2⁶¹¹⁵ + 1 are the only known primes of the form 47 * 2ⁿ + 1. [Ballinger and Keller]