OPERATING UNIT NUMBER DETERMINATION DEVICE, OPERATING UNIT NUMBER DETERMINING SYSTEM, OPERATING UNIT NUMBER DETERMINATION METHOD, AND PROGRAM

An obtaining unit obtains store-visitor number information indicating a store-visitor number, which is a number of customers who visited a store, waiting customer number information indicating a waiting customer number, which is a number of customers waiting to be processed at a plurality of cash registers installed in the store, and influx number information indicating an influx number, which is a number of customers added to the waiting customer number. An influx number prediction unit calculates a predicted influx number, which is a number of customers who are expected to be added to the waiting customer number at the plurality of cash registers after a predetermined time from a current time point, based on the store-visitor number information and the influx number information. A storage unit stores processing capability information indicating a processable quantity that can be processed by each of the plurality of cash registers per a certain time and cost information about an operating cost of each of the plurality of cash registers. A congestion degree prediction unit calculates a plurality of values of a predicted waiting customer number, which is a number of customers who are expected to wait to be processed at the plurality of cash registers after the predetermined time, based on the waiting customer number information, the predicted influx number, and the processing capability information, where each of the plurality of values corresponds to each of a plurality of operating unit numbers of the plurality of cash registers. An operating unit number determination unit calculates an operating unit number of the plurality of cash registers based on the predicted waiting customer number and the cost information.