Yes, when I wound up with Fidelity for a 401(k) I found their system was designed around being able to "enter your password on your phone" -- using the number keys, i.e. b3G -> 234. I can only hope that version is at least stored as a hash...

The worst feeling is getting halfway through keying out your password on the number keys when the Fidelity robot tells you that's not the right password. I just say operator now until they transfer me to a human.

I apparently am "good" enough to never have had that happen, though I don't call very often. That's horrific, since it implies that it is stored as plaintext, "optimistically" as "plain-number-text."

It's also horrific because you can use that to brute-force guess someone's password, because the robot will tell you when you have the wrong digit, so you can work your way through all 10 phone keys for each digit, noting each time whether the robot kicks you out, until you guess the entire thing.

To be clear, the input just times out, likely because they don't expect a long random password input. I don't think it's evidence that they can verify a substring of your password.