//STATUS:C++_AC_8MS_11284KB

 #include <functional>

 #include <algorithm>

 #include <iostream>

 //#include <ext/rope>

 #include <fstream>

 #include <sstream>

 #include <iomanip>

 #include <numeric>

 #include <cstring>

 #include <cassert>

 #include <cstdio>

 #include <string>

 #include <vector>

 #include <bitset>

 #include <queue>

 #include <stack>

 #include <cmath>

 #include <ctime>

 #include <list>

 #include <set>

 //#include <map>

 using namespace std;

 //#pragma comment(linker,"/STACK:102400000,102400000")

 //using namespace __gnu_cxx;

 //define

 #define pii pair<int,int>

 #define mem(a,b) memset(a,b,sizeof(a))

 #define lson l,mid,rt<<1

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

 #define PI acos(-1.0)

 //typedef

 typedef long long LL;

 typedef unsigned long long ULL;

 //const

 const int N=;

 const int INF=0x3f3f3f3f;

 const int MOD=,STA=;

 const LL LNF=1LL<<;

 const double EPS=1e-;

 const double OO=1e15;

 const int dx[]={-,,,};

 const int dy[]={,,,-};

 const int day[]={,,,,,,,,,,,,};

 //Daily Use ...

 inline int sign(double x){return (x>EPS)-(x<-EPS);}

 template<class T> T gcd(T a,T b){return b?gcd(b,a%b):a;}

 template<class T> T lcm(T a,T b){return a/gcd(a,b)*b;}

 template<class T> inline T lcm(T a,T b,T d){return a/d*b;}

 template<class T> inline T Min(T a,T b){return a<b?a:b;}

 template<class T> inline T Max(T a,T b){return a>b?a:b;}

 template<class T> inline T Min(T a,T b,T c){return min(min(a, b),c);}

 template<class T> inline T Max(T a,T b,T c){return max(max(a, b),c);}

 template<class T> inline T Min(T a,T b,T c,T d){return min(min(a, b),min(c,d));}

 template<class T> inline T Max(T a,T b,T c,T d){return max(max(a, b),max(c,d));}

 //End

 LL p[N][];

 LL ans,n,cnt;

 void dfs(LL d,LL phi)

 {

     if(d==cnt){

         ans+=phi;

         return ;

     }

     dfs(d+,phi);

     phi=phi/p[d][]*(p[d][]-);

     for(int i=;i<=p[d][];i++)

         dfs(d+,phi);

 }

 int main(){

  //   freopen("in.txt","r",stdin);

     int i,j,la;

     LL t;

     scanf("%lld",&n);

     cnt=;

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

         if(t%i==){

             p[cnt][]=i;

             while(t%i==){

                 p[cnt][]++;

                 t/=i;

             }

             cnt++;

         }

     }

     if(t)p[cnt][]=t,p[cnt][]=,cnt++;

     ans=;

     dfs(,n);

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

     return ;

 }