Are blue whales the strongest sea creature?

Its the toughest alive today but there were sharks back then that were way tougher.

Two were Cretoxyrhina Mantelli and Carcharocles Megalodon. Cretoxyrhina grew up to 25 ft! Larger by two feet but that's still a pretty big deal! Carcharocles Megalodon could have been 65ft long(3 times the length of a 20 ft Great White Shark!) and weighed 100 tons!(As heavy as a blue whale!). This Shark was the Top predator. It also had a bite force of 20 tons!(It could crush a car in its jaw!), also supporting the idea it was the top predator of all time.