The real name of the Bill Gates is William Henry Gates III. Nowadays he is known as Bill Gates (III), where "III" means the order of third (3rd). By converting the letters of his name to the ASCII-values (which are used in computers) you will get the following:
B I L L G A T E S 3
66 + 73 + 76 + 76 + 71 + 65 + 84 + 69 + 83 + 3 = 666
* Adolf Hitler
* Joseph Stalin
* The Pope
(You can count number 666 from each of the names above.)