43308631298509

This number is a prime.

                                                             4330 8631298509

43308631298509 = (2^2 + 3^3 + 5^5 + 7^7 + 11^11 + 13^13)/7. That's because 2^2 + 3^3 + 5^5 + 7^7 + 11^11 + 13^13 is a semiprime. 2^2 is a semiprime. No other semiprime 2^2 + 3^3 + 5^5 + 7^7 + ... + Prime[n]^Prime[n] is known, at least through n = 57 (last term = 271^271), which is a composite 653-digit number not yet fully factored. [Post]