Problem

2019 AIME II Problem 9

Call a positive integer $n$ $k$ -*pretty* if $n$ has exactly $k$ positive divisors and $n$ is divisible by $k$ . For example, $18$ is $6$ -pretty. Let $S$ be the sum of the positive integers less than $2019$ that are $20$ -pretty. Find $\tfrac{S}{20}$ .

Leading zeroes must be inputted, so if your answer is 34, then input 034

Full credit goes to MAA for authoring these problems. These problems were taken on the AOPS website.

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Problem Tags: Number theory

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Category: AIME II
Points: 4
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