17971

This number is a prime.

+ The smaller of the only two five-digit palindromic primes formed from two primes (17 and 971), one of which is the sum of the digits of the other. [Silva]

+ The smallest palindromic prime that splits up in two ways into both reversals of two emirps: (17, 971) ; (179, 71). [Beedassy]

+ The 17971st and 17972nd triangular numbers are the first consecutive pair of triangular number to have at least 1000 prime numbers between them (1010). [Gaydos]

+ A palindromic prime whose periodic final digits of the sequence are centered hexagonal numbers. [Green]

+ A palindromic prime p such that sod(p)^nod(p) + sigma(p)^d(p) is prime. Note that nod = number of digits. [Sariyar]

(There are 3 curios for this number that have not yet been approved by an editor.)

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