What is the routing number for alpaca's brokerage accounts?

I already know how to link my bank accounts using the web interface for alpaca,
but I want to know what the routing number would be for my alpaca financial account.
Basically I’m wanting to link my alpaca account to my bank the same way my bank account is linked to my alpaca account <–>, as well as being able to transfer funds from other (non-linked) accounts.

I was able to find my account number under banking, but no hint pertaining to any routing number.

I searched these forums, the web, and tinkered around with the interface as best as I could but wasn’t able to come up with any routing number I can use to transfer funds with.