Primality proof for n = 709927:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=16903.html>16903 is prime.</a>
<br>b^((n-1)/16903)-1 mod n = 471067, which is a unit, inverse 242120.
<p>(16903) divides n-1.
<p>(16903)^2 > n.
<p>n is prime by Pocklington's theorem.