Coin toss using random numbers does not appear exactly random

I wanted a random number generator to simulate a coin toss and here's what i did

public class CoinToss
{
    public static void main(String args[])
    {
        int num=(int)(1000*Math.random());
        if(num<500)
            System.out.println("H");
        else
            System.out.println("T");
    }
}

The results were discouraging as i got 16 Heads and 4 tails in 20 runs. That does not appear to be random. Its possible but i want a general opinion if the program is correct ? Am i missing something mathematically ?