13

This number is a prime.

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The smallest idoneal emirp. [Loungrides]

The smallest emirp Delannoy number. [Loungrides]

The only prime less than a googol of form (2^x+1)/5, (case x=6). [Loungrides]

The number of primes formed by inserting two zeros between the digits of a double-digit number: 1009, 2003, 3001, 4001, 4003, 4007, 5003, 5009, 6007, 7001, 8009, 9001, 9007. [Loungrides]

There are thirteen 4-digit primes each consisting of four successive digits, i.e., 1423, 2143, 2341, 2543, 4231, 4253, 4523, 4567, 4657, 5647, 5867, 6547, 6857. [Loungrides]

(There are 4 curios for this number that have not yet been approved by an editor.)