Primality proof for n = 7224223543:
<p>Take b = 2.
<p>b^(n-1) mod n = 1.
<p><a href=70825721.html>70825721 is prime.</a>
<br>b^((n-1)/70825721)-1 mod n = 2424040767, which is a unit, inverse 1336047102.
<p>(70825721) divides n-1.
<p>(70825721)^2 > n.
<p>n is prime by Pocklington's theorem.