Aubameyang had worn the number 17 shirt during his time with Dortmund, which is already occupied by Alex Iwobi at the Emirates Stadium.
He also has ties to the number seven after wearing it for Saint-Etienne and including it in his social media handles, but it was taken by friend Henrikh Mkhitaryan earlier this month.
For Gabon, Aubameyang typically wears number nine. Alexandre Lacazette, the man he replaced as the Gunners' record signing, is the individual who currently has that jersey at Arsenal.
It left the recently vacated number 14 as an obvious choice for the 28-year-old.
Theo Walcott had worn it for 10 years prior to his recent move to Everton, but it was Arsenal legend and all-time top goalscorer Thierry Henry who really made it famous in north London.
Upon his arrival, Aubameyang even commented on his own likeness to Henry.
"The club has such a big history and great players like Thierry Henry. He's an example for us strikers. I'm a fast player and I score goals too, like Henry a little bit. I think I have to work a lot to be like him, but I will do," he said.
Arsenal fans will hope to see Aubameyang make his debut when Everton visit the Emirates in the Premier League on Saturday evening.