Primality proof for n = 117411509:
Take b = 2.
b^(n-1) mod n = 1.
163 is prime.
b^((n-1)/163)-1 mod n = 39742528, which is a unit, inverse 102025030.
157 is prime.
b^((n-1)/157)-1 mod n = 23857135, which is a unit, inverse 20957351.
(157 * 163) divides n-1.
(157 * 163)^2 > n.
n is prime by Pocklington's theorem.