True about Na+ - K+ pump is that
In Na+- K+ exchange, 3 Na+ goes out and 2K+ goes into the cell with the utilization of ATP. 
Hence it is a primary active transport. Due to the net flow of Na+ outwards, there is a potential difference that occurs.
Involves ATPase activity
It can move Na+ in and out of cell
Electrically neutral
Pumps out one Na+ for one K+