1217

This number is a prime.

+ The smallest 4-digit prime p such that the sum of the predecessor and successor primes is divisible by 29. [Russo]

+ The smallest 4-digit prime such that, if its digits are ABCD, AB+CD, and A+B+C+D, they are also each prime. [Opao]

+ The smallest emirp whose additive and multiplicative persistences both equal its prime digital root. [Beedassy]

+ Smallest prime p such that (13^p+9^p)/(13+9) is also prime. [Luen]

+ The first prime p greater than 3 such that 10*p-3 is a perfect cube. [Ewing]

+ The smallest emirp to have invertible prime prime index. [Bajpai]

+ The smallest emirp having an emirp prime index p with reversal q such that q-th prime is also an emirp. [Beedassy]

+ Only non-titanic emirp, that is the product of a repunit number and all its truncations minus four, i.e., 111*11*1-4. [Gupta]

+ The first prime of the form (A^B)*B+(C^D)*D, where A,B,C,D are consecutive Fibonacci numbers (in this case 1,2,3,5). Are there others? [Leonardis]

(There is one curio for this number that has not yet been approved by an editor.)

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