#include <bits/stdc++.h>

using namespace std;

using ll = long long;

constexpr char newl = '\n';

ll calc(ll x, ll lim) {
    ll res = 0;
    while (x >= lim) {
        res += x;
        x >>= 1;
    }
    return res;
}

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

    ll d;
    cin >> d;

    ll lim = 1;
    ll ans = d;
    while (true) {
        ll ng = 0, ok = d;
        while (ok - ng > 1) {
            ll mid = (ok + ng) / 2;
            (calc(mid, lim) >= d ? ok : ng) = mid;
        }
        if (calc(ok, lim) == d) {
            ans = ok;
            break;
        }
        lim <<= 1;
    }
    cout << ans << newl;

    return 0;
}