1621

This number is a prime.

+ ``The'' thanksgiving feast celebrated by the Pilgrams of Plymouth Colony with members of the Massasoit tribe and celebration of the first harvest, October 1621.

+ The mouth of a prime volcano. 1621 is a prime that remains prime when preceded and followed by one, two, three, or four 3's:

    1621 
   316213 
  33162133
 3331621333
333316213333
[Post]

+ The smallest prime whose the reversal is a brilliant number equal to the product of two double-digit emirps, i.e., R(1621)=1261=13*97. Can you find the only other such prime? [Loungrides]

+ The smallest prime p such that p*(p+1) is a multidigit palindromic number. [Gupta]

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

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