#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll=long long;
using ld=long double;
ld pie=3.141592653589793;
ll inf=14449999999999999;
ll mod=998244353;
int main(){
    ll n;
    cin >> n;
    ll ans=n-1;
    for (ll i = 2; i >=0; i++)
    {
        bool ok=false;
        for (ll j = 2; j >=0; j++)
        {
            ll x=0;
            ll now=1;
            for (ll k = 0; k < i; k++)
            {
                if (x>n)
                {
                    break;
                }
                x+=now;
                now*=j;
            }
            if (x>n)
            {
                break;
            }
            
            if (n%x==0&&n/x<j)
            {
                ok=true;
                ans=j;
                break;
            }
        }
        if (!ok)
        {
            break;
        }
    }
    cout << ans << endl;
}