23

This number is a prime.

Single Curio View:   (Seek other curios for this number)
There are 23 known natural numbers n such that 2n does not contain the digit 2. Their sum ends with 23, which is one of them. The prime cases are easy to remember: 2, 3, 23 and ... the 23th prime! [Capelle]

Submitted: 2009-06-10 10:06:38;   Last Modified: 2011-02-20 12:33:07.
Printed from the PrimePages <primes.utm.edu> © G. L. Honaker and Chris K. Caldwell