Pittsburgh won for the 13th time in 14 games, with the lone loss in that stretch having come in overtime. The Penguins moved within two points of the idle New York Rangers for the best record in both the Atlantic Division and the Eastern Conference.
Malkin opened the scoring 1:23 into the game and the Penguins ran off the first four goals of the contest. His slap shot 1:59 into the third period produced his 45th goal of the season, second-best in the NHL.
Pascal Dupuis, Matt Cooke and Chris Kunitz also scored for Pittsburgh, which has not lost in regulation time since Feb. 19 at Buffalo. James Neal had four assists and Sidney Crosby, playing for the fifth time in his most recent return from concussion issues, assisted on two goals.
Radulov is back with the Predators after winning two MVP awards in Russia's professional league.
Pekka Rinne allowed five goals on 23 shots.