2381
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 5 curios for this number that have not yet been approved by an editor.)
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