Well it's one of many code numbers, like 33, for instance, is popular one I covered in a post awhile back. 11, 22, I don't know that many because I haven't read a lot on it yet. But, they are frequently used when it comes to msm reporting. 666 is usually used more so to do with products, advertising and other media.
There's also a lot of symbol use. And again, I only know a few of them. However, the ones I do know, I can spot as easily as the number codes I've learned.
They all have dual purposes both through communication and normalization.