Modulo for encryption

The Developer Student Club requires a good modulo for their encryption algorithms used for their app. They decided to generate a modulo using the following algorithm: Given a pair of adjacent primes $p1, p2$ ( $p2$ > $p1$ and $p2$ is the very next prime after $p1$) the modulo is the smallest number $M$ whose last digits are $p1$ and $M$ is divisible by $p2$, that is, if $p1 = 5$ and $p2 = 7$ t