#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <iomanip>
#include <cmath>
#include <stdio.h>
#include <queue>
#include <deque>
#include <cstdio>
#include <set>
#include <map>
#include <bitset>
#include <stack>
#include <cctype>
using namespace std;
long long n;
int main() {
	cin >> n;
	for (long long j = 2; j <= 1000000; j++) {
		long long co = 0;
		long long now = 1;
		while (co <= n) {
			co += now;
			if (n % co == 0 && n / co < co) {
				cout << j << endl;
				return 0;
			}
			if (1000000000000 / now < j) {
				break;
			}
			now *= j;
		}
	}
	long long ans = 1000000000000000;
	for (long long i = 1; i * i <= n; i++) {
		if (n % i == 0 && n / i - 1 > i) {
			if (ans > n / i - 1) {
				ans = n / i - 1;
			}
		}
	}
	cout << ans << endl;
}