This number is a composite.
539994 = 2 x 3 x 7 x 13 x 23 x 43 and 5^2 + 3^3 + 9^7 + 9^13 + 9^23 + 4^43 is prime. [De Geest]
539994 = 2 x 3 x 7 x 13 x 23 x 43 and 5^2 + 3^3 + 9^7 +
9^13 + 9^23 + 4^43 is prime. [De Geest]