Primality proof for n = 49481:

Take b = 2.

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

1237 is prime.
b^((n-1)/1237)-1 mod n = 17090, which is a unit, inverse 30369.

(1237) divides n-1.

(1237)^2 > n.

n is prime by Pocklington's theorem.