Numero Uno might make a habit of cheating the system with his mathematical talents, but he's fairly laidback even when it boomerangs to bite him. Of course, having a fortune from owning a chain of stores to fall back on and committing only light illegal activities does make life easy for him even when jail time is involved.
It is unknown who his voice actor is.
With a knack for numbers in hand, Uno worked his way to ownership of a chain of stores, which he got even more profit out of by messing with his bookkeeping. This hasn't gone unpunished but chances are the setbacks aren't going to leave an impression on him.
A man who takes his luxurious life as it comes, Uno isn't one to surrender himself to stress or anger. Carpe Diem works just fine for him and if that is shortsighted, it has effectively yet to be proven to be so.
Numero Uno is a muscular rhinoceros with a taste for the simple elegance of turtleneck sweaters.
Uno serves jail time in the St. Canard Minimum Security Prison for tax evasion. When his lawyers, who had lost him the case and he still hadn't paid, are abducted, Darkwing Duck suspects him to be the brain behind it and tries to abduct him from prison to get answers. Darkwing's incompetence and false accusation don't earn him Uno's regard or notice as he takes his time finishing a game of golf, sunbathing, and barbecuing until Darkwing stops bothering him.