A 13 hour book is probably 120,000 words in length (narrators tend to run about 9,300 words per finished hour).
That's a fairly long book. If we cut that back to a smaller novel the numbers get even worse. You'd need to have 1,000 people fully-listen to your audiobook to get the same kind of money I quoted above with a 60,000 word title.
It takes longer than an hour for a narrator to finish a complete hour of finalized ACX-quality narration.
ACX themselves say this:
We have found that it generally takes a total of around 6.2 hours for a Producer to complete one hour of an Audiobook.
6.2 hours per finished hour...
That's 80.6 hours for a 13 hour 120,000 word title, or 40.3 hours for a 6.5 hour 60,000 word book.
500 full-listens @ 50% narrator split on a 13 hour book = $186 for the narrator...
Federal minimum wage is $7.25 per hour. 80.6 hours of that is over $584
The narrator would be earning $2.31 per hour for this effort assuming they hit the success of 500 full listens on a 13 hour book.
You'd need 1,569 full listens of a 120,000 word book before your narrator would be taking home minimum wage for their time and effort... half that if you're self-narrating.
You'd need 1.22 million minutes listened to in order for your narrator to make minimum wage for their time on a royalty split 50/50 13 hour title.