The factors of the number 1,018,440 are: 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 18, 20, 23, 24, 27, 30, 36, 40, 41, 45, 46, 54, 60, 69, 72, 82, 90, 92, 108, 115, 120, 123, 135, 138, 164, 180, 184, 205, 207, 216, 230, 246, 270, 276, 328, 345, 360, 369, 410, 414, 460, 492, 540, 552, 615, 621, 690, 738, 820, 828, 920, 943, 984, 1035, 1080, 1107, 1230, 1242, 1380, 1476, 1640, 1656, 1845, 1886, 2070, 2214, 2460, 2484, 2760, 2829, 2952, 3105, 3690, 3772, 4140, 4428, 4715, 4920, 4968, 5535, 5658, 6210, 7380, 7544, 8280, 8487, 8856, 9430, 11070, 11316, 12420, 14145, 14760, 16974, 18860, 22140, 22632, 24840, 25461, 28290, 33948, 37720, 42435, 44280, 50922, 56580, 67896, 84870, 101844, 113160, 127305, 169740, 203688, 254610, 339480, 509220, 1018440.
If you add them up, you will get the total of 3,628,800.