Primality proof for n = 250162337:

Take b = 2.

b^(n-1) mod n = 1.

7817573 is prime.
b^((n-1)/7817573)-1 mod n = 42207566, which is a unit, inverse 237712881.

(7817573) divides n-1.

(7817573)^2 > n.

n is prime by Pocklington's theorem.