2227777domain: NPropertiesPrimalityPrimeyesAppears in sequencesa(n) = largest prime factor of n^n + 1.at n=11A007571Primes that contain digits 2 and 7 only.at n=19A020459Largest prime factor of 12^n - 1.at n=23A366718Largest prime factor of 12^n+1.at n=12A366720Prime numbersat n=164565