The difference between the number of people and the number of people lies in their different meanings. Number of people refers to the total number of people. Usually, figures are used for specific statistics, and sometimes they are estimated in a general range. The number of people represents the sum of several times, including the number of repeated people. The number of people is "the total number of people who appear repeatedly in an activity (such as visiting and receiving) in unit time".

So it's not the total number of times/total number of people, but the number of people is the total number of times. Talk about the "number of people" who watched the film during its release (that is, the number of times that can be counted repeatedly in the case of one person, one vote). The difference between "person-time" and "number of people" is that the number of times can be counted repeatedly for the same person.