Calcium/calmodulin-regulated and magnesium-dependent enzyme that catalyzes the hydrolysis of ATP coupled with the transport of calcium out of the cell (PubMed:8530416). By regulating sperm cell calcium homeostasis, may play a role in sperm motility (By similarity). . This is the function of ENSG00000058668 (ATP2B4, ATPase plasma membrane Ca2+ transporting 4).