821

This number is a prime.

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

+ 2^821+821^3 is the 2nd prime and the largest non-titanic prime of form 2^p+p^3, where p is a prime. The previous such prime is 157. [Loungrides]

+ The smallest prime in the largest 3-digit prime quadruplet, {821, 823, 827, 829}, whose sums of digits are the terms of the only double-digit quadruplet, {11, 13, 17, 19}. [Loungrides]

(There is one curio for this number that has not yet been approved by an editor.)

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