Antiprime Numbers

A positive integer is called an antiprime (also known as a highly composite number) if it has strictly more divisors than every positive integer smaller than it. For example, $1, 2, 4, 6, 12, 24$ are all antiprimes.

Given an integer $n$, write a program that finds the largest antiprime that is not greater than $n$.

The first line contains a single integer $n$ ($1 \le n \le 2000000000$).

Print, on a single line, the largest antiprime that is not greater than $n$.