#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<(int)(n);i++)
using namespace std;
using ll = long long ;
using P = pair<int,int> ;
using pll = pair<long long,long long>;
constexpr ll INF = 1e9;
constexpr long long LINF = 1e17;
constexpr int MOD = 1000000007;
constexpr double PI = 3.14159265358979323846;

int main(){
    ll d;
    cin >> d;
    ll ans = LINF;

    auto ok = [&](ll m,ll i){
        ll res = m;
        rep(j,i){
            res += m/2;
            m /= 2;
        }
        return res;
    };

    rep(i,70){
        ll l = -1,r = d+1;
        while(r - l > 1){
            ll m = (l + r)/2;
            if(ok(m,i) >= d) r = m;
            else l = m; 
        }
        if(ok(r,i) == d) ans = min(ans,r);
    }

    cout << ans << endl;

    return 0;
}