Question 149
An integer $n$ is perfect if the sum of its divisors is $2n$. Let $n$ be a perfect integer and $p$ its smallest prime divisor. Prove that the exponent of $p$ in the factorization of $n$ into a product of prime powers is even.
Math Olympiad Vault · MathNet 2018-part-02 — 181 problems (EN–VI)