491
This number is a prime.
Just showing those entries submitted by 'Carmichael': (Click here to show all)
491 is a Sophie Germain prime. 491 is also a divisor
of a Generalized Fermat Number, as 491 * (2^123281+1)
divides GF(123280,10) = 10^(2^123280) + 1. [Carmichael]
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