You do not have enough information to calculate the electrical power consumed during operation.
The three quantities listed, 1260 kcal/hr, 1.47 kW and 5000 BTU/hr, all represent the same power level, simply given in different units. They all give, as stated, the cooling capacity: the rate of heat energy removal from the cooled space.
A particular air-conditioner has a dimensionless number called the Coefficient of Performance. It is defined as the ratio of Energy Removed to Energy Consumed. This value, usually around 4 to 8, divided into your cooling capacity (preferably in kW), will give the electrical power consumption of the unit when running...