Can you have more than one trusted phone number, for Two-Factor Authentication on iPhone?

Anagaid:

Not sure what the “upper limit” might be but DO know that you can have at-least four (4x) Trusted Numbers.

Note that Trusted Numbers normally do NOT receive the “broadcast style” 2FA verification codes (as received on Trusted Devices) …

.. they only receive them individually; and only after you specifically select THAT particular number. (after clicking the “Didn’t Receive Code” link)

Yes, you should have 2 if possible.

Add the second number as follows:

Tap Settings

Tap Your Name at the top of the screen

Tap Sign In & Security to edit things