/*
 This program calculates the value of euler totient funtion for a given n
*/
public class euler
{

/*
 Funtion to check whether a given number is prime or not
*/
public static boolean isprime(int k)
{
	int i,m;
        boolean flag=false; 
        
        if(k==1)
                return false; 
        else if(k==2)
                return true;  
        for(i=2;i<=k-1;i++)
	{
		m=k%i;
               	if(m==0)
                {
                   return flag;
                }
        }
        return true;
}    


public static void main(String args[])
{

	int x,i,t;
        boolean flag;
        int j;
        int n=1;  
        int d=1;     
  
        x = Integer.parseInt(args[0]);
  
        for(i=2;i<x;i++)
        {
             t=x%i;  
             if(t==0)
             {
                 flag=isprime(i);
                 if(flag==true)
                 {
                   j = (i-1);
                   n = n*j; /// here we will store the neuminator and denominator separately
                   d = d*i; /// and do the division at the last step
                 }    	  
             }
        }
        
        n=(n*x)/d;

        System.out.println("The value of euler totient function is  "+n);
} 
}