Description

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

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

Output a single line containing a positive integer p, which is the larger prime factor.

21

7

Source

CodesOnline