Primality proof for n = 473471:
Take b = 2.
b^(n-1) mod n = 1.
419 is prime.
b^((n-1)/419)-1 mod n = 462977, which is a unit, inverse 360540.
113 is prime.
b^((n-1)/113)-1 mod n = 331310, which is a unit, inverse 391197.
(113 * 419) divides n-1.
(113 * 419)^2 > n.
n is prime by Pocklington's theorem.