Primality proof for n = 1746439:
Take b = 2.
b^(n-1) mod n = 1.
10037 is prime. b^((n-1)/10037)-1 mod n = 1203711, which is a unit, inverse 262036.
(10037) divides n-1.
(10037)^2 > n.
n is prime by Pocklington's theorem.