//#include <atcoder/all>
#include <iostream>
#include <numeric>
#include <cmath>
#include <limits>
#include <stdio.h>
#include <iomanip>
#include <string> // string, to_string, stoi
#include <vector> // vector
#include <algorithm> // min, max, swap, sort, reverse, lower_bound, upper_bound
#include <utility> // pair, make_pair
#include <tuple> // tuple, make_tuple
#include <cstdint> // int64_t, int*_t
#include <cstdio> // printf
#include <map> // map
#include <queue> // queue, priority_queue
#include <set> // set
#include <stack> // stack
#include <deque> // deque
#include <unordered_map> // unordered_map
#include <unordered_set> // unordered_set
#include <bitset> // bitset
#include <cctype> // isupper, islower, isdigit, toupper, tolower
using namespace std;
//using namespace atcoder;
using ll = long long;
#define all(A) A.begin(),A.end()
using vll = vector<ll>;
#define rep(i, n) for (long long i = 0; i < (long long)(n); i++)
using Graph = vector<vector<int>>;

vector<ll> ISP;
ll M = 1500005;
void PP(ll M) {
	ISP.assign(M + 1, -1);
	for (ll i = 2; i <= M; i++) {
		ISP[i] = i;
	}

	ISP[0] = -1;
	ISP[1] = -1;
	for (ll i = 2; i * i <= M; i++) {
		if (ISP[i] == i) {

			for (ll j = 2; i * j <= M; j++) {
				if (ISP[i * j] != i * j)continue;

				ISP[i * j] = i;
			}
		}
	}


}

vector<ll> Dk(70);
ll mod = 1e9 + 7;
void Ks(ll K) {
	rep(i, 70) {
		Dk[i] = 0;
	}
	Dk[0] = K;
	rep(i, 69) {
		Dk[i + 1] = Dk[i] * Dk[i];
		Dk[i + 1] %= mod;
	}
}
ll GG(ll Ps) {
	ll P = Ps;
	ll res = 1;
	rep(i, 70) {
		if (P % 2 != 0) {
			res *= Dk[i];
			res %= mod;
		}
		P /= 2;
	}
	return res;
}

int main() {
	ll N;
	cin >> N;
	for (ll i = 2; i * i <= N; i++) {
		set<ll> S;
		ll M = N;
		while (M > 0) {
			S.insert(M % i);
			M /= i;
		}
		if (S.size() == 1) {
			cout << i << endl;
			return 0;
		}
	}
	cout << N - 1 << endl;
}