Primality proof for n = 4815314615204347717321:

Take b = 3.

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

2585077427327 is prime.
b^((n-1)/2585077427327)-1 mod n = 1930801824996032704834, which is a unit, inverse 2365398961448627848130.

(2585077427327) divides n-1.

(2585077427327)^2 > n.

n is prime by Pocklington's theorem.