#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n);i++)
#define sz(x) int(x.size())
typedef long long ll;
typedef long double ld;
typedef pair<int,int> P;

int main() {
  ll n;
  cin >> n;
  ll res = n;
  for (ll x = 1; x * x <= n; x++) {
    if (n % x == 0) {
      if (x > 2 && x % 2 != 0) res = min(res, x);
      if (x != n / x) {
        if ((n / x > 2 ) && (n / x) % 2 != 0) res = min(res, n / x);
      } 
    }
  }
  cout << res << endl;
  return 0;
}