# 659

This number is a prime.

floor(659/6)=109, floor(659/5)=131, floor(659/9)=73. All prime. 23 also has this property. Are there others? (No 0's or 1's in the candidate!) [Wood]

The first occurrence of a twin prime pair (659, 661) one of which is strobogrammatic and the other one invertible when read on a calculator (7-segment digital display). Note that the latter when turned upside down becomes also the larger member of another twin prime pair (197, 199). [Beedassy]

0659, 2659, 3659, 5659, and 6659 are all primes. [Forouhati]

(There are 4 curios for this number that have not yet been approved by an editor.)

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