This number is a prime.

+ The prime 2381 is the 35th Centered Square Number. Note that 35 = (2 + 3) x (8 - 1). [Post]

+ The sum of the first n squares that are also reverse primes when n = 5. The smallest prime with this property. [Gaydos]

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

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