#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return true; } return false; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return true; } return false; }
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define mp make_pair
#define si(x) int(x.size())
const int mod=998244353,MAX=200005;
const int INF=1<<30;
//const ll INF=1LL<<60;

int main(){
    
    std::ifstream in("text.txt");
    std::cin.rdbuf(in.rdbuf());
    cin.tie(0);
    ios::sync_with_stdio(false);
    
    ll D;cin>>D;
    ll left=0,right=D;
    while(right-left>1){
        ll mid=(left+right)/2;
        ll sum=0;
        ll now=mid;
        while(now){
            sum+=now;
            now/=2;
        }
        if(sum>=D) right=mid;
        else left=mid;
    }
    for(ll i=right;i<=D;i++){
        ll sum=0;
        ll now=i;
        while(now){
            sum+=now;
            now/=2;
            if(sum>D) break;
            
            if(sum==D){
                cout<<i<<endl;
                return 0;
            }
        }
    }
}