Many American films and TV shows use fake telephone numbers beginning with 555 when a phone number is mentioned, to avoid the possibility of using a real phone number and potentially causing grief to the owner when idiots try calling the number mentioned.

Firstly, I find that this practice is one that inevitably breaks my suspension of disbelief when watching such a production, because it's so blatantly obvious that what is happening is a fiction.

Secondly, it's sad that there are so many people so unutterably stupid as to make this a real concern.

On the gripping hand, if you haven't called your mother for a while, give her a call. Let her know you were prompted to do so by one of those "crazy Internet things".