A random number generating device includes: a random number generator configured to have a plurality of random number generating elements that generate a random number in response to supply of a spin-injection current; and a temperature controller. The first radiation unit is created by multiple circuits of different shapes that are interconnected to form a three-dimensional configuration. A heating unit can heat the detection element. The registrar completes the registration of the domain name with the appropriate registry. The output control it controls a generator output based on a first target value decided corresponding to a command value indicated by the command signal, when the revolution number of the generator is less than the reference revolution number, and controls the generator output based on a second target value in place of the first target value.