1 #include <iostream>
2 #include <cstdio>
3 #include <cstring>
4
5 using namespace std;
6 typedef long long LL;
7
8 LL Eular(LL m)
9 {
10 LL res = m;
11 for(LL i=2; i*i<=m; i++)
12 {
13 if(m%i==0)
14 {
15 res -= res/i;
16 while(m%i==0)
17 m /= i;
18 }
19 }
20 if(m > 1)
21 res -= res/m;
22 return res;
23 }
24
25 int main()
26 {
27 LL m;
28 while(~scanf("%lld",&m))
29 {
30 LL ans = 0;
31 for(LL i=1; i*i<=m; i++)
32 {
33 if(m%i == 0){
34 ans += Eular(m/i)*i;
35 if(m != i*i)
36 ans += m/i*Eular(i);
37 }
38 }
39 cout<<ans<<endl;
40 }
41 return 0;
42 }
