Prism is the name of Nutanix central management platform used for all hypervisors as well as file services. Prism is an integral part of the AOS platform and as such resilient to failures.
Prism offers a subset of the most frequently used VMware management operations (VM Create, VM Update, VM Delete, VM Power On/Off Operations, Launch Console, Clone). Prism is not meant as a replacement alternative for the VMware vCenter console, as it covers only a subset.
Nutanix Acropolis Hypervisor (AHV) is based on KVM and offers a full-service managing environment on top of this.