Primality proof for n = 3286873:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=15217.html>15217 is prime.</a>
<br>b^((n-1)/15217)-1 mod n = 2482492, which is a unit, inverse 360874.
<p>(15217) divides n-1.
<p>(15217)^2 > n.
<p>n is prime by Pocklington's theorem.