Primality proof for n = 6418733:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=84457.html>84457 is prime.</a>
<br>b^((n-1)/84457)-1 mod n = 2105383, which is a unit, inverse 1942126.
<p>(84457) divides n-1.
<p>(84457)^2 > n.
<p>n is prime by Pocklington's theorem.