1. An image capturing apparatus comprising: an image capturing element which receives subject light incident via a photographing lens, converts the subject light into a captured image signal, and outputs the signal; an A/D conversion section which converts the captured image signal outputted by the image capturing element into image data and outputs the image data; a storage section which stores at least the image data outputted by the A/D conversion section; a registration section which relates identification facial images which are image data to be used as criteria for identifying faces of subjects among the image data stored in the storage section to identification information of each subject, and registers related data into a database; a facial image extraction section which extracts facial images which are facial portion regions of a person from photographed images which are desired image data outputted by the A/D conversion section and stored in the storage section; an identification section which identifies from the database an identification facial image matching an extracted facial image which is a facial image extracted by the facial image extraction section; and a photograph quantity calculation section which calculates for each subject identification information a photograph quantity which is the total number of photographed images from which an extracted facial image matching an identification facial image corresponding to identification information for each subject has been extracted.