98689

This number is a prime.

+ The smallest palindromic circular-digit prime. [De Geest]

+ The first centered triangular number (i.e., of the form the form of (3n2 - 3n + 2)/2) that is a palindromic prime. [Trotter]

+ The smallest prime that remains prime when inserting one, two, three, four, or five zeros between each digit (908060809, 9008006008009, etc.). [Vrba]

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

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