Powell helped the Cardinal (6-3) dominate in the paint, where Stanford outscored the Pioneers 34-14.
Royce O’Neale scored 17 points for the Pioneers (1-5), who lost their fourth straight.
Stanford, which started a 13-day break for finals after the game, never trailed. The Cardinal built an early 21-6 advantage and Denver, which has not scored more than 68 points in a contest this season, never got closer than 10 the rest of the way.
Chris Udofia added 10 points for the Pioneers, who have not beaten Stanford since 1972 and have lost five straight. Jalen Love and Cam Griffin each added 10 points.
Powell, who scored 19 in the first half, made his first six shots in helping the Cardinal to a 35-19 halftime lead.