The factors of the number 3,629,640 are: 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 15, 20, 21, 24, 28, 29, 30, 35, 40, 42, 56, 58, 60, 70, 84, 87, 105, 116, 120, 140, 145, 149, 168, 174, 203, 210, 232, 280, 290, 298, 348, 406, 420, 435, 447, 580, 596, 609, 696, 745, 812, 840, 870, 894, 1015, 1043, 1160, 1192, 1218, 1490, 1624, 1740, 1788, 2030, 2086, 2235, 2436, 2980, 3045, 3129, 3480, 3576, 4060, 4172, 4321, 4470, 4872, 5215, 5960, 6090, 6258, 8120, 8344, 8642, 8940, 10430, 12180, 12516, 12963, 15645, 17284, 17880, 20860, 21605, 24360, 25032, 25926, 30247, 31290, 34568, 41720, 43210, 51852, 60494, 62580, 64815, 86420, 90741, 103704, 120988, 125160, 129630, 151235, 172840, 181482, 241976, 259260, 302470, 362964, 453705, 518520, 604940, 725928, 907410, 1209880, 1814820, 3629640.
If you add them up, you will get the total of 12,960,000.