#include<iostream>
#include<math.h>
#include<fstream>
using namespace std;

int main()
{
	ifstream in;
	ofstream out;
	in.open("pair.in");
	out.open("pair.out");
	unsigned long double n;
	unsigned long long i,j,rez;
	rez = 1;
	in >> n;
	for(i = 1;i < n;i++)
	{
		for(j = 1;j < n;j++)
		{
			if(i % j ==0)
				rez++;
		}
	}
	int result = rez+sqrt(n);
	if(n == 1)
		result = 1;
	out<<result<<endl;
	return 0;
}