Description

If a positive integer $n$ greater than or equal to $1$ satisfies that the divisor of all positive integers less than $n$ and greater than or equal to $1$ is less than the divisor of $n$, then $n$ is an Antiprime.
For example: 1, 2, 4, 6, 12, 24, they are all antiprimes.

Please calculate the maximum antiprime number that is not greater than $n$.

Format

Input

A line of positive integers $n$.

Output

Contains only one integer, i.e. the largest antiprime number that is not greater than $n$.

Samples

1000

830

Limitation

$1 \le n \le 2 \times 10^9$