1619
This number is a prime.
Just showing those entries submitted by 'Beedassy': (Click here to show all)
The smallest nonprime-digit emirp that remains a
nonprime-digit emirp when each digit is replaced by its
complement (9491). Note that it is also the smallest
nonprime-digit emirp that remains an emirp when sandwiched
between a pair of prime digits (316193) and that the sum of
digits is prime in all cases. [Beedassy]
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