People usually don't make up slang for things with short names, such as numbers.
It is slang for bowel movement
For
Indium is a chemical element with an atomic number of 49. There is no slang for this word.
A "Grand" is slang for 1000
It means your telephone number.
Doop is slang for dope which can be used to describe something as cool, or it can be slang for a number of drugs.
Number cruncher
PITA
shiv
bb stands 4 byebye.
The Slang term for a fifty cent coin is a half a buck or 4 bits.
The meaning of YTB is slang on the internet for You're the Best. There are a number of other common slang terms such as LOL (laugh out loud) and TTYL (talk to you later).