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

//--------------------

FILE * f=fopen ("fractii.in","r");
FILE * g=fopen ("fractii.out","w");

long int d,total,divizori,n;
//--------------------
void cit()
{
fscanf (f,"%ld",&n);
}
//--------------------
void tip()
{
fprintf (g,"%d",total);
}
//--------------------
void calc()
{
total=n*n-n+1-2*divizori;
}
//--------------------
void div()
{
for (d=2;d<=sqrt(n);d++)
{
	if (n%d==0)
	{
	divizori++;
	}
}
}
//--------------------
int main()
{
cit();
div();
calc();
tip();
fclose(f);
fclose(g);
return 0;
}
//--------------------