What would you definition of this be?
An intellectual prowess is a display of exceptionally high intelligence and knowledge. To be highly skilled, knowledgeable at/of something.
Prowess often has a negative connotation though. A person who is self-centered or a braggart may be said to be speaking of their prowess in something, to include intellect. When others speak of prowess it is often satirically said.
A more positive statement might be intellectual capability, capacity and so forth.
Someone who goes to a nudist beach and remembers faces afterwards.
If somebody is far from being good-looking you may praise their intelectual prowess
I love the above 2 comments!