Primality proof for n = 1627771:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=1871.html>1871 is prime.</a>
<br>b^((n-1)/1871)-1 mod n = 910795, which is a unit, inverse 589711.
<p>(1871) divides n-1.
<p>(1871)^2 > n.
<p>n is prime by Pocklington's theorem.