Primality proof for n = 235251347:

Take b = 2.

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

972113 is prime.
b^((n-1)/972113)-1 mod n = 196216934, which is a unit, inverse 80765271.

(972113) divides n-1.

(972113)^2 > n.

n is prime by Pocklington's theorem.