Primality proof for n = 28661:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=1433.html>1433 is prime.</a>
<br>b^((n-1)/1433)-1 mod n = 16779, which is a unit, inverse 16815.
<p>(1433) divides n-1.
<p>(1433)^2 > n.
<p>n is prime by Pocklington's theorem.