Primality proof for n = 31002614113816567181:

Take b = 2.

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

66721073718023 is prime.
b^((n-1)/66721073718023)-1 mod n = 28399559369264978603, which is a unit, inverse 17080331612411478219.

(66721073718023) divides n-1.

(66721073718023)^2 > n.

n is prime by Pocklington's theorem.