You can go back home or read on.

I tried to come up with a a nice 404 page. A good design with some nice words and every time I did something, I hated it after a couple of days. And then it made me think. Why the number 404.

First up, 404 is not the only status code, there are multiple of them; one of the common ones is 404. Also referred as HTTP status codes, these were established by the World Wide Web Consortium (W3C) in 1992, as a part of the HTTP 0.9 spec. They were defined by Tim Berners-Lee, the same person who single-handedly invented the web and the first web browser in 1990. Dissecting 404 - the first 4 means a client error. It's the servers way of saying you did something wrong or messed with the URL. The middle 0 refers to a general syntax error, a spelling mistake to keep it simple and the last 4 means it is part of a specific error group of 40x, which includes other errors. 

404 has factors of 2 x 2 x 101.
404 is also a perfect palindrome.
404 = 20^2 + 2^2
404 area code covers Atlanta, GA and its closes suburbs, roughly within Interstate 285.
Angel Number 404 - search this term and you will be amazed.