There are a plurality of atmans.
Each atman is an eternal, omnipresent, ubiquitous, infinite substance which is the substratum of consciousness.
The atman is a real knower, active agent and passive enjoyer / sufferer (jnatr, kartr, bhoktr). The body is the locus of his experiences, the senses the instruments of experience, and the internal feelings and external things are the objects of his experience.
Consciousness is not the essence of the self. Prabhakara, like N.V., conceives it as an accidental static guna of the atman. The atman is by essence jada, unconscious, and, insofar as moksa is admitted, it means the isolation of the atman from all gunas, and hence also from consciousness and bliss. !!
For Bhatta, consciousness is not a static guna but a modal change (parinama) of the self. it is therefore a dynamic modification, a passing from potency to act. The atman is not simply unconscious, but unconscious-conscious (cid-acid-rupa or jada-bodh-atmaka), namely, characterized by the potency to know which belongs to his very nature (jnana-sakti-svabhava). In moksa, the self is divested of all his qualities and modes, including cognition and bliss, but remains, as in deep sleep, endowed with potential consciousness. (De Smet, Guidelines 223)