#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <queue>
#include <string>
#include <map>
#include <set>
#include <stack>
#include <tuple>
#include <deque>
#include <array>
#include <numeric>
#include <bitset>
#include <iomanip>
#include <cassert>
#include <chrono>
#include <random>
#include <limits>
#include <iterator>
#include <functional>
#include <sstream>
#include <fstream>
#include <complex>
#include <cstring>
#include <unordered_map>
using namespace std;

using ll = long long;
using P = pair<int, int>;
constexpr int INF = 1001001001;
constexpr int mod = 1000000007;
// constexpr int mod = 998244353;

template<class T>
inline bool chmax(T& x, T y){
    if(x < y){
        x = y;
        return true;
    }
    return false;
}
template<class T>
inline bool chmin(T& x, T y){
    if(x > y){
        x = y;
        return true;
    }
    return false;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    ll D;
    cin >> D;
    ll lb = 0, ub = D;
    while(ub - lb > 1){
        ll mid = (lb + ub) / 2;
        ll sum = mid, x = mid;
        while(x > 0){
            sum += x / 2;
            x /= 2;
        }
        if(sum >= D)    ub = mid;
        else    lb = mid;
    }
    ll sum = ub, x = ub;
    bool ok = sum == D;
    while(x > 0){
        sum += x / 2;
        x /= 2;
        ok |= sum == D;
    }
    ll ans = ub;
    if(!ok) ans = D;
    cout << ans << endl;

    return 0;
}