2551

This number is a prime.

+ The smallest prime p such that p2 + p + 4 is a palindrome. [Russo]

+ 2551 = (2*5*5*1)^0 + (2*5*5*1)^1 + (2*5*5*1)^2. [Rooholamini]

+ The only prime, less than a googol, that is reverse concatenation of n first powers of 5 (n=3). [Loungrides]

+ Kosmos-2551 was a Russian reconnaissance satellite that did not make it into orbit. [Estremera]

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

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