Primality proof for n = 53308853141:
Take b = 2.
b^(n-1) mod n = 1.
2665442657 is prime.
b^((n-1)/2665442657)-1 mod n = 1048575, which is a unit, inverse 10565125057.
(2665442657) divides n-1.
(2665442657)^2 > n.
n is prime by Pocklington's theorem.