/*

 * Author:  sweat123

 * Created Time:  2016/6/27 14:01:46

 * File Name: main.cpp

 */

#include<set>

#include<map>

#include<queue>

#include<stack>

#include<cmath>

#include<string>

#include<vector>

#include<cstdio>

#include<time.h>

#include<cstring>

#include<iostream>

#include<algorithm>

#define INF 1<<30

#define MOD 1000000007

#define ll long long

#define lson l,m,rt<<1

#define rson m+1,r,rt<<1|1

#define pi acos(-1.0)

using namespace std;

const int MAXN = ;

int n;

ll ef(int n)

{

    ll cnt = n;

    int i;

    for(i = ; i * i <= n; i++){

        if(n % i == )

        {

            cnt -= cnt / i;      //   (x-x/p1) *(1-1/p2)*(1-1/p3)*(1-1/p4).....

            while(n % i == )

                n /= i;

        }

    }

    if(n > ) cnt -= cnt / n;

    return cnt;

} 

int main(){

    while(~scanf("%d",&n)){

        ll ans = ;

        for(int i = ; i <= (int)sqrt(n); i++){

            if(n % i == ){

                ans += ef(n / i) * i;

                if(n / i != i){

                    ans += ef(i) * (n / i);

                }

            }

        }

        printf("%lld\n",ans);

    }

    return ;

}