CF1000247L

#include <algorithm>
#include <bitset>
#include <deque>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <list>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <vector>

#define fst first
#define snd second
#define all(x) (x).begin(), (x).end()
#define clr(a, v) memset(a, v, sizeof(a))
#define pb push_back
#define mp make_pair
#define sz(x) (int)(x.size())
#define FORN(i,s,n) for(int i=s;i<(int)(n);i++)
#define FOR(i,n) FORN(i,0,n)
#define FORIT(i,x) for( typeof x.begin()  i=x.begin(); i!=x.end(); i++ )
#define trace(x)    cerr << #x << ": " << x << endl;
#define trace2(x, y) cerr << #x << ": " << x << " | " << #y << ": " << y << endl;

using namespace std;

typedef long long int64;
typedef vector <int> vi;
typedef pair <int,int> ii;
typedef vector <string> vs;
typedef vector <ii> vii;

const int INF = 2e9+9;

map <int , int> DP;

int f(int N){
    if (N==1) return 1;
    if (DP.count(N)!=0) return DP[N];
    int ans=N/2+1,c,g;
    for(int i=2;i*i<=N;i++){
        if( N%i==0 ){
            c=i;g=N/i;
            ans=min( ans, (c/2+1)*f(g) );
            swap(c,g);
            ans=min( ans, (c/2+1)*f(g) );
        }
    }
    return DP[N]=ans;
}

int main(){
    int N;
    cin>>N;
    cout<<f(N)<<endl;
}