So, I don't know a ton about this, but I know that you can send text messages as emails. Usually it's phone_number@specialdomain.com. Like, for T-Mobile USA,

So, I don't know a ton about this, but I know that you can send text messages as emails. Usually it's phone_number@specialdomain.com. Like, for T-Mobile USA, I think it's t-zones.com for the domain. You can ask people what provider they have or just SPAM all the possible suffixes and the wrong ones will simply bounce.