Is there a word or words for a group of numbers that is used with a specific meaning apart from the values of the numbers themselves? Like 911 for emergency, 411 for information, 24/7 for always available, or 10-4, 10-20, and similar radio code designations? I know each of these has specific meanings and associations, but I wonder what term/s can be used to refer to this category of numbers used as language.
It is called numeronym: a number based word.
Less commonly, a numeronym is composed entirely of numbers, such as "212" for "New Yorker", "4-1-1" for "information", "9-1-1" for "help", and "101" for "basic introduction to a subject". Words of this type have existed for decades, including those in 10-code, which has been in use since before World War II.