#include <cassert>
#include <iostream>
#include <vector>
using namespace std;
using ll = long long;
ll D;
ll check(ll x, int t) {
	ll res = x;
	while(t--) {
		x /= 2;
		res += x;
		if(res > D) return (ll)3e18;
	}
	return res;

}
int main() {
	cin >> D;
	ll ans = 1e18;
	for(int K = 0; K <= 62; K++) {
		ll ok = D, ng = 0;
		while(ok - ng > 1) {
			ll mi = (ok + ng) / 2;
			(check(mi, K) >= D ? ok : ng ) = mi;
		}
		if(check(ok, K) == D) ans = min(ans, ok);
	}
	cout << ans << endl;
}