What does the phone number nnn mean?

It’s a scammer or a spammer, and it probably means they don’t know how to properly operate whatever they are using to mask their phone number.

It is super easy to fake a caller ID setting by the caller. I have seen calls from 000–000-0000, 999–999-9999, Joe Blow, and others.

Not necessarily a spammer, but probably not a call you want to answer.

Somebody who is trying to trick you into answering your phone out of curiosity. So, just don’t do it. If it’s important, they will leave a message

It’s usually a scammer trying to make you wonder who is calling…wonder enough to answer. Also, IF you call yourself DON’T answer that one either!!! They will spoof your name & number because many will answer out of curiosity to try & figure out who is on the other end.

It means nothing other than it is not a legitimate call. If you are using a mobile phone, you might want to be sure you haven’t inadvertently marked a legitimate number with an ID name of NNN.

Whatever you do with a spammer call, never say the word, “yes”, to a spam caller. They harvest recordings of “yes” and can use that to imitate your approval in identity theft attacks.