Primality proof for n = 1399417:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=58309.html>58309 is prime.</a>
<br>b^((n-1)/58309)-1 mod n = 1383628, which is a unit, inverse 79326.
<p>(58309) divides n-1.
<p>(58309)^2 > n.
<p>n is prime by Pocklington's theorem.