#include <bits/stdc++.h>
#include <math.h>

#include <algorithm>
#include <array>
#include <atcoder/all>
#include <bitset>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <sstream>
#include <vector>

using namespace std;
using namespace atcoder;

using Graph = vector<vector<int>>;

using ll = long long;
typedef pair<ll, ll> P_ll;
typedef pair<int, int> P;

const ll INF_ll = 1e17;
const int INF = 1e8;
template <class T>
bool chmax(T& a, const T& b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
bool chmin(T& a, const T& b) {
  if (b < a) {
    a = b;
    return 1;
  }
  return 0;
}
template <typename T>
using min_priority_queue = priority_queue<T, vector<T>, greater<T>>;

int main() {
  ll D;
  cin >> D;
  ll ans = D;
  for (ll i = max(D / 2 - 100000, 0ll); i <= D / 2 + 100000; i++) {
    ll x = i;
    ll now = 0;
    while (x > 0) {
      now += x;
      if (now == D) {
        chmin(ans, i);
        break;
      }
      x /= 2;
    }
  }

  cout << ans << endl;

  return 0;
}