using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Nhap N:");

        int n=int.Parse(Console.ReadLine());

        int t=1;

        for(int i=1;i<=n/2;i++)

        {if((n%i==0) && i%2==1)

            {t=t*i;}

        }

        Console.WriteLine(t);

    }

}