Why would any one model a "a building number" as a real number.
When does anyone ever need to apply addition, substraction or multiplcation
to a building number
Same goes for telephone numbers! The telephone keybad have characters, mobile keypads have characters of sometimes both a local langugae + english/latin, why would the type that store the result be just numbers.
Telephone numbers can be thought be casted to real number from the receiving variable, plus why would a dialer for example only handler numbers and not map the more elaborate keypad!!!
Strings and Numbers and primitive data types, you should rely more on
abstract data types, think more about ur types