21663 Full Form. Full Meaning of 21663 Find long form and abbreviation, slang or definition of 21663. What does 21663 mean? What does 21663 stand for? We are providing world largest and most comprehensive acronyms, names, abbreviations database directory on the Internet. Our data base contains more than 8,00,000 terms abbreviations and acronyms. You can also search unique terms more than 4,00,000 general Comprehensive words.