Primality proof for n = 2619408491927:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=124781.html>124781 is prime.</a>
<br>b^((n-1)/124781)-1 mod n = 724783470365, which is a unit, inverse 128608519514.
<p><a href=307.html>307 is prime.</a>
<br>b^((n-1)/307)-1 mod n = 2043496089362, which is a unit, inverse 2555564420813.
<p>(307 * 124781) divides n-1.
<p>(307 * 124781)^2 > n.
<p>n is prime by Pocklington's theorem.