//#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
#include <iostream>
#include <algorithm>
using namespace std;
using ll = long long;
using pii = pair<int,int>;
using pll = pair<ll,ll>;
using vi = vector<int>;  using vvi = vector<vi>;
using vl = vector<ll>;   using vvl = vector<vl>;
using vb = vector<bool>; using vvb = vector<vb>;
using vpi = vector<pii>; using vvpi = vector<vpi>;
using vpl = vector<pll>; using vvpl = vector<vpl>;
const int inf = 1 << 30;
const ll INF = 1LL << 60;
#define rep(i,m,n) for (int i = m; i < (int)(n); i++)
#define rrep(i,m,n) for (int i = m; i > (int)(n); i--)

ll p(ll x,ll y){
    ll ju = 1;
    rep(i,0,y){
        if (ju > INF/double(x)) return INF;
        ju *= x;
    }
    return ju;
}

int main(){
    ll n; cin >> n;
    ll ans = n;
    rep(i,2,61){
        ll ok = 0,ng = floor(pow(n,1/(long double)(i)))+10;
        while (ng-ok > 1){
            ll mid = (ok+ng)/2;
            if (p(mid,i) <= n) ok = mid;
            else ng = mid;
        }
        ll xt = pow(ok,i);
        ll ju = ok+i+n-xt;
        ans = min(ans,ju);
    }
    cout << ans << endl;;
}