Primality proof for n = 12545359681:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=1866869.html>1866869 is prime.</a>
<br>b^((n-1)/1866869)-1 mod n = 6908199420, which is a unit, inverse 819548924.
<p>(1866869) divides n-1.
<p>(1866869)^2 > n.
<p>n is prime by Pocklington's theorem.