Vacuum cleaner and vacuum cleaner system

A vacuum cleaner comprising a secondary battery as a driving source, the vacuum cleaner comprising:

• an electric blower driven by electric power supplied by the secondary battery;
• a driving control part configured to control driving of the electric blower;
• a display input part configured to display a first element relevant to operation of the electric blower, and a second element having negative correlation with the first element, and configured to receive input of a temporary setting value of at least either one of the first element and the second element, in a setting mode in which the electric blower is in an off state;
• an arithmetic part configured to obtain a predictive value of the other of the first element and the second element on a basis of the temporary setting value received by the display input part in the setting mode;
• and
• an indication control part configured to make the display input part display the temporary setting value and the predictive value at any time, on a basis of the input of the display input part and the arithmetic part in the setting mode, wherein
• the driving control part starts the electric blower on a basis of the temporary setting value or the predictive value as a true setting value by inputting an instruction to start the vacuum cleaner in the setting mode.