Hello!
I used Decimal to ASCII converter.
I put our numbers 71721075 there.
The converter gave me: ÒK
I do not speak French, but that looks OKAY for me.
There could be other meanings. French words: “aux quais” and “au quai” sounds like “OK” or “Okay”.
“Aux quais” means something like “shipyards” or “to the port”.
“Au Quai” means something like “At the pier”.
Happy hunting!