The number of teeth in whales (known scientifically as cetaceans) varies a lot between species. Some have as many as 250 teeth, while the members of any entire family, the baleen whales lack teeth entirely.

This varies from one whale to another: baleen whales I'm not sure have teeth, or if they do then they are very heavily modified. Toothed whales probably have varying numbers of teeth - I'll bet a sperm whale has more than a dolphin, but I don't actually know the numbers.