Perfect Numbers Java

PROGRAM TO FIND PERFECT NUMBERS


class MAIN
{
      
    // Returns true if n is perfect
    static boolean isPerfect(int n)
    {
        // To store sum of divisors
        int sum = 1;
  
        // Find all divisors and add them
        for (int i = 2; i * i <= n; i++)
        {
            if (n % i==0)
            {
                if(i * i != n)
                    sum = sum + i + n / i;
                else
                    sum = sum + i;
            }
        } 
        // If sum of divisors is equal to
        // n, then n is a perfect number
        if (sum == n && n != 1)
            return true;
  
        return false;
    }
  
    // Driver program
    public static void main (String[] args)
    {
        System.out.println("Below are all perfect" +                             "numbers till 10000");
        for (int n = 2; n < 10000; n++)
            if (isPerfect(n))
                System.out.println( n + " is a perfect number");
    }
}

OUTPUT
Below are all perfect numbers til 10000
6 is a perfect number
28 is a perfect number
496 is a perfect number
8128 is a perfect number

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