This number is a prime.

                                                             6081 8091990661

+ The smallest invertible prime p containing all of the invertible digits formed from the reverse concatenation of two consecutive Strobogrammatic primes, i.e., {6081809, 1990661}. Curiously, p is also expressible as the sum of two squares: (7065631^2+3300750^2). [Bajpai]

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