1990661

This number is a prime.

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

+ The smallest Cyclops strobogrammatic prime formed by inserting a zero between an emirp and its invertible prime. Note that (199, 661) is the 2nd pair of 3-digit prime rotative twins. [Loungrides]

Printed from the PrimePages <t5k.org> © G. L. Honaker and Chris K. Caldwell