n<=100000000

  #include<stdio.h>
 #include<string.h>
 #include<math.h>

int flag[10006];
 int num[10000],total,now,n;

void solve(int index,int Mul,int K){
       int i,t;
    if(K==0){
     now+=n/Mul;
     return;
    }
    for(i=index;i<total-K+1;i++){
      Mul*=num[i];
      t=now;
      if
 
(Mul<=n){
               solve(i+1,Mul,K-1);
      }
      if(t==now)//優化剪枝（1）
       return;
            Mul/=num[i];
    }
 }

int Judge(int x){
  int t,i;
  t=sqrt(x*1.0);
  for(i=2;i<=t;i++)
   if(n%i==0)
    return 0;
  return 1;
 }

int main(){
     int i,j,t,Count;
  memset(flag,0,sizeof(flag));
  for
 
(i=2;i<=10000;i++){
   if(flag[i])
    continue;
   for(j=2;j*i<=10000;j++)
    flag[i*j]=1;
  }
  while(scanf("%d",&n)==1){
   Count=0;
   if(n<=10000){
    for(i=2;i<n;i++)
     if(!flag[i])
      Count++;
   }
   else{
    t=sqrt(1.0*n);
    total=0;
    for(i=2;i<=t;i++)
     if(!flag[i])
      num[total++]=i;
    for
 
(i=1;i<=total;i++){
     now=0;
     solve(0,1,i);
     if(now==0)//優化(2)
      break;
     if(i&1)
        Count+=now;
     else
        Count-=now;
    }
    Count-=total;
    Count=n-Count-1;
    if(Judge(n))
     Count--;
   }
   printf("%d\n",Count);
  }
  return 0;
 }