Why is it best to store a telephone number as a string vs. integer?

Question

As the question states, why is it considered best practice to store telephone numbers as strings rather than integers in the telephone_number column?

Not sure I understa

Answer 1

There is several reasons for this :

• Phone numbers often start with a "0" : an integer will remove all leading "0"s
• Phone number can have special char : +, (, -, etc. (for exemple : +33 (0)6 12 23 34)
• You cannot perform operations on phones : adding phones, for instance, would be meaningless
• Phone number may be internationalised, i.e. different format for different people, thus not possible with integers

There might be other reasons, but I guess that's already a fair amount of those :)