#include<bits/stdc++.h>
using namespace std;
int p[500]={1,2,4,6,12,24,36,48,60,120,180,240,360,720,840,1260,1680,2520,5040,7560,10080,15120,20160,25200,27720,45360,50400,55440,83160,110880,166320,221760,277200,332640,498960,554400,665280,720720,1081080,1441440,2162160,2882880,3603600,4324320,6486480,7207200,8648640,10810800,14414400,17297280,21621600,32432400,36756720,43243200,61261200,73513440,110270160,122522400,147026880,183783600,245044800,294053760,367567200,551350800,698377680,735134400,1102701600,1396755360,2001000000};
int main()
{
    int n;
    freopen("ant.in","r",stdin);
    freopen("ant.out","w",stdout);
    cin>>n;
    int ans;
    for(int i=0;;i++)
    {
        if(p[i]>n) {
            cout<<p[i-1]<<endl;
            return 0;
        }
    }
    return 0;
}