h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I heard that it actually came from some beliefe that numbers have meanings and that repeating the same number makes the meaning stronger. 6 was a bad number or meant evil or something. So repeating it three times meant it was the worst thing.

As you can see, I'm not very smart and that makes it easy for you to make fun of me. So go ahead! I'm used to it.

Well yes that's correct actually, in Hebrew repeating something three times emphasises it strongly. In Revelation (the last book of the Bible) Heaven is described; and in one place it talks about some creatures who worship God by saying 'Holy, holy, holy' and something else, I can't remember. But by saying Holy three times they emphasise it.
One theory is that as well as 3, 7 is a perfect/holy number (7 days in God's creation, for example). 6 is one less than 7, therefore imperfect. And 666 emphasises it by repeating it three times.

There's lots of other theories; I managed to find a simple process to convert the name 'Bill Gates' to '666', for example

Bwahahahaaa!!

I didn't think Satan whould be so nice like that.

999 is the number of the Australian Devil.

Or, alternatively, the number of the British Devil from an Australian perspective.

I had a teacher which the gymatry of her name was 666... she was realy a satan. speaking of doing stuff tree times- look at the tree dots at the end of this sentence...

"Bwahahahaaa!!"

p.s.- sorry for forgetung the "H"s