Bear in mind that, especially with old/ancient historical records, so much can be lost in 'translation' - that is, the fudging (more or less) of dates to cement the idea of a mythical figure as emperor, or simply in conflicting records, or even in the misunderstanding of certain phrases. Even the Wikipedia itself mentions that "No firm dates can be assigned to this emperor's life or reign," further casting doubt on the supposed dates they lived through.