/**************************************************************Problem: 2705User: zhangheranLanguage: C++Result: AcceptedTime:28 msMemory:89184 kb
****************************************************************/#pragma GCC optimize (2)
#include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;
int cnt;
int prime[10000010];
int phi[10000010];
bool ins[10000010];
void Euler()
{phi[1]=1;for(int i=2;i<=10000000;i++){if(!ins[i]) prime[++cnt]=i,phi[i]=i-1;for(int j=1;j<=cnt&&i*prime[j]<=10000000;j++){ins[i*prime[j]]=true;if(i%prime[j]==0){phi[i*prime[j]]=phi[i]*prime[j];break;}else phi[i*prime[j]]=phi[i]*(prime[j]-1);}}return ;
}
long long getphi(long long n)
{
//  if(n<10000000) return phi[n];long long res=n;for(long long i=2;i*i<=n;i++){if(n%i==0) res=res/i*(i-1);while(n%i==0) n/=i;}if(n>1) res=res/n*(n-1);return res;
}
long long x;
long long ans;
int main()
{
//  freopen("1.in","r",stdin);
//  freopen("1.out","w",stdout);scanf("%lld",&x);
//  Euler();long long i=1;for(;i*i<x;i++) if(x%i==0) ans+=i*getphi(x/i)+(x/i)*getphi(i);if(i*i==x) ans+=i*getphi(i);printf("%lld",ans);
}
//9812