1289

This number is a prime.

+ This Sophie Germain prime is also a twin prime, and the smallest prime having distinct or increasing digits and exactly 5 permutations of its digits prime. [Hasler]

+ Concatenate (left-to-right) the 1st, 2nd, 8th, and 9th prime and you will get another prime, i.e., 231923. [Loungrides]

(There are 9 curios for this number that have not yet been approved by an editor.)

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