2023 APMO Problems/Problem 2

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Problem

Find all integers $n$ satisfying $n \ge 2$ and $\frac{\sigma(n)}{p(n)-1}$, in which $\sigma(n)$ denotes the sum of all positive divisors of $n$, and $p(n)$ denotes the largest prime divisor of $n$.

Solution

https://youtu.be/xkIm0k1FE-8