#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<bitset>
#include<set>
#include<map>
#include<stack>
#include<queue>
#include<deque>
#include<list>
#include<iomanip>
#include<cmath>
#include<cstring>
#include<functional>
#include<cstdio>
#include<cstdlib>
#include<numeric>
using namespace std;

#define repr(i, a, b) for (int i = (int)(a); i < (int)(b); i++)
#define rep(i, n) repr(i, 0, n)
#define INF 2e9
#define MOD 1000000007
//#define MOD 998244353
#define LINF (long long)4e18
#define jck 3.141592

const double EPS = 1e-10;

using ll = long long;
using Pi = pair<int,int>;
using Pl = pair<ll,ll>;


int main(){
    ll n; cin >> n;
    if(n == 1 || n == 2){
        cout << n+1 << endl;
        return 0;
    }
    for(ll i = 2; i*i < n; i++){
        ll d = n%i;
        ll ni = i;
        bool ok = true;
        while(ni <= n){
            if(n/ni%i != d) ok = false;
            ni *= i;
        }
        if(ok){
            cout << i << endl;
            return 0;
        }
    }
    ll ans = n-1;
    for(ll i = 2; i*i <= n; i++){
        if(n%i == 0){
            ll m = n/i;
            if(m-1 > i){
                ans = min(ans,m-1);
            }
        }
    }
    cout << ans << endl;
}