Good article explaining the risks today of using texts for second-factor authentication. E-mails are no better as they can be delayed and are usually in plain text.
Note too that although there is often mention of the Google Authenticator app, you can actually use any authenticator app, even to authenticate into Google services. I prefer to use Authy as it has consistently been ahead of Google's own app, having search capability, easily replication between multiple devices (or to new devices) including my desktop.
Some password managers like LastPass, 1Password and Bitwarden have built-in support for 6-digit authentication already that not many folks are aware of.
Most popular services on the Internet today offer authenticator app support, so you want to spend a minute on each just setting it up - you won't have to thank yourself later as you're probably unlikely to have those accounts hacked in future.
See There’s a better way to protect yourself from hackers and identity thieves
If you’re using texts for two-factor authentication, it’s time to change to an app. Here’s what you need to know.