Uh, okay. My account isn't even registered to a phone number, never has been, and my mobile devices aren't registered with Google.
I'm currently only signed into Google on my laptop, and if I do happen to sign into another device (which has happened before), Google just drops me an email something along these lines..
'A new device has logged into your account. If this wasn't you, click here, but if it was you, there's nothing you need to do'