Aren't phone numbers longer than they used to be?
OK, technically my parent's number was 10 digits rather than 5 because it was <areacode>577099, but that didn't matter as I'd almost always be local to that code, and if not could state my home town if talking to an adult who was doing the calling (or if I'd dialled the operator number, which I'd need to do anyway for a revere-charges call) and they'd know that bit.
https://en.wikipedia.org/wiki/List_of_Georgia_area_codes
Of course, they're increasingly meaningless now that everyone has cell phones and gets to pick an area code.