Primality proof for n = 163810856527:
Take b = 2.
b^(n-1) mod n = 1.
27301809421 is prime.
b^((n-1)/27301809421)-1 mod n = 63, which is a unit, inverse 59803963494.
(27301809421) divides n-1.
(27301809421)^2 > n.
n is prime by Pocklington's theorem.