i Register
In some senses, brainpower is marked as idiomatic. Watch for register when choosing this word.
noun
Mental ability; intelligence.
He applied his brainpower to the problem.
Intelligent people considered or regarded as a group.
I suspect the think tank lacks the brainpower to function effectively.
“Brainpower rankings usually identify the usual suspects: college towns like Boston, Washington, D.C., and the San Francisco Bay area. And to be sure, these places generally have the highest per capita education levels.”