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

What Neil Slater said is correct. I would add that there are lots of edge cases where you can't express a telephone number as a number value consistently.

For example, consider these numbers:

011-123-555-1212
+11-123-555-1212
+1 (112) 355-5121 x2

These are all potentially valid phone numbers, but they mean very different things. Yet, in integer form, they are all 111235551212.