Primality proof for n = 2420633:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=302579.html>302579 is prime.</a>
<br>b^((n-1)/302579)-1 mod n = 255, which is a unit, inverse 265795.
<p>(302579) divides n-1.
<p>(302579)^2 > n.
<p>n is prime by Pocklington's theorem.