Yes, male sperm whales possess testes, which are the equivalent of "balls" in other mammals. However, unlike most terrestrial mammals, their testes are internal, located within the abdominal cavity rather than in an external scrotum.

Size: Sperm whale testes are remarkably large, particularly in mature males. A single testis can weigh up to 500 kilograms (over 1,100 pounds), making them among the largest testes in the animal kingdom, both in absolute size and relative to body mass. This enormous size is thought to be an adaptation related to sperm competition, where larger sperm reserves can increase reproductive success.

Source