Description

Given that a positive integer n is the product of two distinct prime numbers, find the larger prime number.

Input Format

The input consists of a single line containing a positive integer n.
For 60% of the data, $6 ≤ n ≤ 1000$.
For 100% of the data, $6 ≤ n ≤ 2×10^9$.

Output Format

The output consists of a single line containing a positive integer p, which is the larger prime number.

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