Primality proof for n = 33871:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=1129.html>1129 is prime.</a>
<br>b^((n-1)/1129)-1 mod n = 31123, which is a unit, inverse 18279.
<p>(1129) divides n-1.
<p>(1129)^2 > n.
<p>n is prime by Pocklington's theorem.