Primality proof for n = 5195037399650551:
Take b = 2.
b^(n-1) mod n = 1.
3848175851593 is prime.
b^((n-1)/3848175851593)-1 mod n = 3354906414016591, which is a unit, inverse 4474818534150531.
(3848175851593) divides n-1.
(3848175851593)^2 > n.
n is prime by Pocklington's theorem.