Sperm whales are toothed whales, while right whales are baleen whales. The right whales are usually smaller than the sperm whales and are more vulnerable to human beings attacking them. The sperm whale also has a large head that is a third of its body length, which contains the spermaceti organ.
No. They both are two distinct subspecies of the whale family. Blue Whales are the largest known species of animal ever known to man. Sperm whales are around 20 meters long while blue whales can be around 30 meters long and weigh twice as much as sperm whales.