How to assign an attribute to a specific product without other products in the same class inheriting

I have a requirement to add a phone number attribute to a specific product, but that product is part of a product class that has other products in it.When I created an attribute on that class, all products got the attribute but I just need it for a specific one. I'm thinking of hiding the attribute on the other products but the class got hundreds of products so I'm looking for other solutions.