#include <iostream> #include <string> #include <sstream> #include <stack> #include <algorithm> #include <cmath> #include <queue> #include <bitset> #include <iomanip> #include <limits> #include <chrono> #include <random> #include <array> #include <unordered_map> #include <functional> #include <complex> #include <numeric> #include <cctype> #include <map> #include <set> #include <cstdlib> #include <bitset> #include <tuple> #include <assert.h> #include <deque> template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } constexpr long long INF = 1LL << 60; constexpr int inf = 1000000007; constexpr long long mod = 1000000007LL; //constexpr long long mod = 998244353LL; using namespace std; typedef long long ll; ll power(ll x, ll n) { if (n == 0) { return 1; } if (n % 2 == 0) { return power(x * x, n / 2); } else { return x * power(x, n - 1); } } ll f(ll X, ll c) { ll t = pow(X, 1.0 / (double)c); ll res = INF; for (ll i = max(0LL, t - 1000); i <= t + 1000; i++) { if (power(i, c) >= X) { chmin(res, i); break; } } return res; } int main() { cin.tie(nullptr); ios::sync_with_stdio(false); ll a; cin >> a; ll res = a; for (ll i = 1; i <= 60; i++) { chmin(res, i * f(a, i)); } cout << res << endl; }