FN made something like a One-Point-Two Million of these before 1940. During this same time frame Colt made 500,000 or so themselves. FN doesn't have great records at the time and with 2 world wars crossing the Belgian frontier you can imagine why. Some sources say FN got to the million mark before 1914 others say it was 550,000. WW1 stopped production of the pocket gun, then picked back up at a trickle post war to the 30's when it was discontinued. (And some would argue was replaced by the "Baby" Browning) Model 1906's continued to be made out from spare parts as late as 1959. Yours appears to be an 'late' model, based on the trigger shape (post 1911) and shape of the safety lever.
Serial numbers 180,000--aprox 1,200,000 are of this 'late type'. Still, you very likely have a Pre WW1 pistol.
These are sweet little striker fired pistols. Brownings don't have the same magazine safety as some Colts do. Yours may or may NOT have the magazine safety. Supposedly the late model does, but transitional models might lack it.
Unload it (carefully--the firing pin acts as the ejector, vigorously clearing it could lead to an accidental firing) drop the magazine, cock it and see if it dry fires.