Primality proof for n = 224563:
Take b = 2.
b^(n-1) mod n = 1.
2879 is prime. b^((n-1)/2879)-1 mod n = 197262, which is a unit, inverse 115255.
(2879) divides n-1.
(2879)^2 > n.
n is prime by Pocklington's theorem.