#include <cstdio>
#include <iostream>
using namespace std;

long long f(long long x, int k) {
    long long ans = 0;
    for (int i = 0; i < k; i++) { ans += x; x /= 2; }
    return ans;
}

long long solve(long long d) {
    long long ans = d;
    for (int k = 1; k <= 60; k++) {
        long long lb = 0, ub = d;
        while (ub - lb > 1) {
            long long m = (ub + lb) / 2;
            if (f(m, k) < d) lb = m;
            else ub = m;
        }
        if (f(ub, k) == d) ans = min(ans, ub);
    }
    return ans;
}

int main() {
    long long d; cin >> d;
    cout << solve(d) << endl;
}