/**
 *    author:  otera    
**/
#include<bits/stdc++.h>
using namespace std;

#define int long long
typedef long long ll;
typedef long double ld;
#define rep(i, n) for(int i = 0; i < n; ++ i)
#define per(i,n) for(int i=n-1;i>=0;i--)
typedef pair<int, int> P;
typedef pair<ll, ll> LP;
#define fr first
#define sc second
#define all(c) c.begin(),c.end()
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

void solve() {
    auto f = [&](ll x, int k) {
        ll ret = x;
        rep(i, k) {
            x >>= 1;
            ret += x;
        }
        return ret;
    };
    ll d; cin >> d;
    ll ans = d;
    for(int k = 1; k <= 62; ++ k) {
        ll ok = d, ng = 0;
        while(ok - ng > 1) {
            ll mid = (ok + ng) / 2;
            if(f(mid, k) >= d) ok = mid;
            else ng = mid;
        }
        if(f(ok, k) == d) chmin(ans, ok);
    }
    cout << ans << "\n";
}

signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	//cout << fixed << setprecision(20);
	//int t; cin >> t; rep(i, t)solve();
	solve();
    return 0;
}