10101869
This number is a prime.
The smallest Honaker prime containing all of the invertible
digits {0, 1, 6, 8, 9}; when rotated by 180 degrees
(10101869 -> 69810101) it remains a Honaker prime. [Bajpai]
The smallest Honaker prime P, containing all of the
strobogrammatic digits {0, 1, 6, 8, 9}, yields another
Honaker prime Q when rotated by 180 degrees. Curiously, P
and Q both are expressible as the sum of two squares. [Bajpai]
Printed from the PrimePages <t5k.org> © G. L. Honaker and Chris K. Caldwell