This number is a prime.

+ The only near-repdigit seven-digit palindromic wing prime such that the product of itself and all truncations of itself minus one, i.e.,7772777*777277*77727*7772*777*77*7-1 = 1528503743076224921408830427 is prime. [Bajpai]

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

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