You haven't given us any choices to pick from. But I have a feeling that you're not talking about names like Ralph, Bob, or Jacob, so I'll take some guesses from the names of sets that numbers are commonly organized into:
The number ' 2 ' is ...
-- a real number
-- a rational number
-- a positive number
-- an integer
-- a counting number
-- a natural number
-- a whole number
-- a prime number
-- an even number