Primality proof for n = 10485409823782909:

Take b = 2.

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

11636921 is prime.
b^((n-1)/11636921)-1 mod n = 5405584624689910, which is a unit, inverse 7910347825997103.

55579 is prime.
b^((n-1)/55579)-1 mod n = 5677608841230753, which is a unit, inverse 2829817572263935.

(55579 * 11636921) divides n-1.

(55579 * 11636921)^2 > n.

n is prime by Pocklington's theorem.