#include<iostream>
#include<cmath>
#include<vector>
#include<cassert>
using namespace std;
int gcd(int a,int b)
{
	while(b)
	{
		int t=a%b;
		a=b;
		b=t;
	}
	return a;
}
long N;
int pf[1<<20];
long quo(long a,long v){return(double)a/v;}
int main()
{
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	for(int i=2;i<1<<20;i++)if(pf[i]==0)
	{
		for(int j=i;j<1<<20;j+=i)pf[j]=i;
	}
	cin>>N;
	long ans=0;
	for(int m=2;;m++)
	{
		long up=quo(N,2*m);
		int l=m+1,r=(int)min(up,2*m-1L);
		if(l>r)break;
		//for(int nm=l/2*2+1;nm<=r;nm+=2)if(gcd(m,nm)==1)ans+=up/nm;
		vector<int>ps;
		{
			int v=m;
			while(v%2==0)v/=2;
			ps.push_back(2);
			while(v>1)
			{
				int p=pf[v];
				ps.push_back(p);
				while(v%p==0)v/=p;
			}
		}
		long sum=0;
		for(int i=0;i<1<<ps.size();i++)
		{
			int t=1;
			for(int j=0;j<ps.size();j++)if(i>>j&1)t*=ps[j];
			int nl=quo(l+t-1,t),nr=quo(r,t);
			long nup=quo(up,t);
			long cur=0;
			while(nl<=nr)
			{
				long q=quo(nup,nl);
				int nnl=(int)min((long)nr,quo(nup,q));
				cur+=q*(nnl-nl+1);
				nl=nnl+1;
			}
			//for(int j=nl;j<=nr;j++)cur+=nup/j;
			if(__builtin_parity(i))sum-=cur;
			else sum+=cur;
		}
		ans+=sum;
	}
	cout<<ans<<endl;
}