Ore Number Program in Java

Ore number is a positive integer whose divisors have a harmonic value as an integer. Ore number is also known as harmonic divisor number.

For example, 6 has four factors: 1, 2, 3 and 6.

Harmonic mean of the factors is:
4 / (1 + 1 / 2 + 1 / 3 + 1 / 6) = 2

The harmonic mean of the factors of 6 is 2, which is an integer.

So, 6 is an Ore number or harmonic divisor number.

Write a program in Java to input an integer and check whether it is an Ore Number or not.

import java.io.*;
class Ore{
    public static void main(String args[])throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        System.out.print("Enter the number: ");
        int num = Integer.parseInt(br.readLine());
        int f = 0;
        double mean = 0.0;
        for(int i = 1; i <= num; i++){
            if(num % i == 0){
                f++;
                mean += 1.0 / i;
            }
        }
        mean = f / mean;
        if(mean == (int)mean)
            System.out.println(num + " is an Ore Number.");
        else
            System.out.println(num + " is NOT an Ore Number.");
    }
}