Where can I find the Device Account Number?

The Device Account Number, sometimes referred to as your Apple Pay Card Number, can be found by opening the Wallet app, tapping the card, and then tapping the (***)  symbol in the top right corner. Depending on your version of iOS and the Wallet App you may be given a drop down menu, in which case you can select 'card details' and will will be shown there as your Apple Pay card number or if taken to a single account detail page you can find it by scrolling down to find Device Account Number.