#include <bits/stdc++.h>
using namespace std;

using i64 = long long;

i64 jump(i64 d, int t) {
    i64 ret = 0;
    for(int i = 1; i <= t; i ++) {
        ret += d;
        d /= 2;
    }
    return ret;
}

int main() {
    i64 d, ans = 1e18;
    cin >> d;
    for(int i = 1; i <= 70; i ++) {
        i64 l = 0, r = 1e18;
        while(l + 1 < r) {
            i64 mid = (l + r) / 2;
            if(jump(mid, i) < d) l = mid;
            else r = mid;
        }
        if(jump(r, i) == d) ans = min(ans, r);
    }
    cout << ans;
}