#include <bits/stdc++.h>
using namespace std;
using ll = int_fast64_t;
constexpr int mod = 1e9 + 7;
constexpr int inf = (1 << 30) - 1;
constexpr ll infll = (1LL << 61) - 1;
#define fast() ios::sync_with_stdio(false), cin.tie(nullptr)
#define set_digit(N) cout << fixed << setprecision((N))
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")

ll func(ll x, ll D)
{
	ll sum = 0;
	while (x > 0 && sum < D)
	{
		sum += x;
		x /= 2;
	}
	return sum;
}

int main()
{
	ll D, ans = infll;
	cin >> D;
	ll mi = max((ll)1, D / 2 - 50000000);
	for (ll i = mi; i <= min(D, D / 2 + 50000000); i++)
	{
		if (func(i, D) == D)
			ans = min(ans, i);
	}
	cout << ans << "\n";
}