Primality proof for n = 26312496861293:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=108763483.html>108763483 is prime.</a>
<br>b^((n-1)/108763483)-1 mod n = 14625306561131, which is a unit, inverse 23204593613389.
<p>(108763483) divides n-1.
<p>(108763483)^2 > n.
<p>n is prime by Pocklington's theorem.