49081

This number is a prime.

+ In 1999, Harvey Dubner discovered that R49081 = (10^49081-1)/9 was a repunit probable prime.

+ A Cyclops prime that is the concatenation of three square numbers: 49 = 7^2, 0 = 0^2, and 81 = 9^2. [Ruiz-Huidobro]

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