691

This number is a prime.

Single Curio View:   (Seek other curios for this number)
The only known prime number which is a square when turned upside down (169) and another square when reversed (196). Note that 169 and 196 are the smallest consecutive squares using the same digits. [Capelle]

Submitted: 2007-02-21 16:11:21;   Last Modified: 2008-05-26 01:12:04.
Printed from the PrimePages <t5k.org> © G. L. Honaker and Chris K. Caldwell