We call a positive integer an antiprime if it has more divisors than any positive integer less than that number. Example antiprime numbers are: 1, 2, 4, 6, 12, 24.</p>

Write a program which:

• reads from the standard input a positive integer n,
• computes the largest antiprime number not greater than n,
• writes the result to the standard output.

The first and only line of standard input contains a single integer n, 1 ≤ n ≤ 2,000,000,000.

출력 형식

In the only line of standard output your program should write one integer - the largest antiprime number not greater than n.

예제 입력

1000

예제 출력

840