4 (sometimes called Four) is one of the numbers that lives on Number Island. He is the second in command of 1234567890, and is 8's parole officer. 4 is currently a master golf player (people are always calling him for help) and sometimes considered an important figure in the answering of the Answer to the Ultimate Question of Life, the Universe, and Everything.
4 was born on Number Island, but decided that most of the numbers were stupid. He didn't want to be stupid, so he learned how to be smart. He became so smart, he got the attention of their king, 2. 2 taught 4 how to be a police officer, and 4 also became the second in command of Number Island.
4 decided that he wanted to help people, so he started volunteering. Then he realized he doesn't like work, so he quit volunteering, and started charging as much as he could. 4 is now very wealthy, but not enough to by a fancy car, so 4 is very sad now.
But As X Returned From His Break, 4 Tried To Rule The World.