Prime Numbers Magnets
Description: Twenty-three is the ninth prime number, the smallest odd prime that is not a twin prime. Twenty-three is also the fifth factorial prime,[1] the second Woodall prime.[2] It is an Eisenstein prime with no imaginary part and real part of the form 3n − 1. 23 is the third base-10 repunit prime exponent after 2 and 19.[3] The fifth Sophie Germain prime[4] and the fourth safe prime,[5] 23 is the next to last member of the first Cunningham chain of the first kind to have five terms (2, 5, 11, 23, 47). Since 14! + 1 is a multiple of 23 but 23 is not one more than a multiple 14, 23 is a Pillai prime.[6] 23 is the smallest odd prime to be a highly cototient number, as the solution to x − φ(x) for the integers 95, 119, 143, 529.[7] 23 is the firs...
