The factors of the number 16,561,440 are: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 24, 28, 30, 31, 32, 35, 36, 40, 42, 45, 48, 53, 56, 60, 62, 63, 70, 72, 80, 84, 90, 93, 96, 105, 106, 112, 120, 124, 126, 140, 144, 155, 159, 160, 168, 180, 186, 210, 212, 217, 224, 240, 248, 252, 265, 279, 280, 288, 310, 315, 318, 336, 360, 371, 372, 420, 424, 434, 465, 477, 480, 496, 504, 530, 558, 560, 620, 630, 636, 651, 672, 720, 742, 744, 795, 840, 848, 868, 930, 954, 992, 1008, 1060, 1085, 1113, 1116, 1120, 1240, 1260, 1272, 1302, 1395, 1440, 1484, 1488, 1590, 1643, 1680, 1696, 1736, 1855, 1860, 1908, 1953, 2016, 2120, 2170, 2226, 2232, 2385, 2480, 2520, 2544, 2604, 2790, 2968, 2976, 3180, 3255, 3286, 3339, 3360, 3472, 3710, 3720, 3816, 3906, 4240, 4340, 4452, 4464, 4770, 4929, 4960, 5040, 5088, 5208, 5565, 5580, 5936, 6360, 6510, 6572, 6678, 6944, 7420, 7440, 7632, 7812, 8215, 8480, 8680, 8904, 8928, 9540, 9765, 9858, 10080, 10416, 11130, 11160, 11501, 11872, 12720, 13020, 13144, 13356, 14787, 14840, 14880, 15264, 15624, 16430, 16695, 17360, 17808, 19080, 19530, 19716, 20832, 22260, 22320, 23002, 24645, 25440, 26040, 26288, 26712, 29574, 29680, 31248, 32860, 33390, 34503, 34720, 35616, 38160, 39060, 39432, 44520, 44640, 46004, 49290, 52080, 52576, 53424, 57505, 59148, 59360, 62496, 65720, 66780, 69006, 73935, 76320, 78120, 78864, 89040, 92008, 98580, 103509, 104160, 106848, 115010, 118296, 131440, 133560, 138012, 147870, 156240, 157728, 172515, 178080, 184016, 197160, 207018, 230020, 236592, 262880, 267120, 276024, 295740, 312480, 345030, 368032, 394320, 414036, 460040, 473184, 517545, 534240, 552048, 591480, 690060, 788640, 828072, 920080, 1035090, 1104096, 1182960, 1380120, 1656144, 1840160, 2070180, 2365920, 2760240, 3312288, 4140360, 5520480, 8280720, 16561440.
If you add them up, you will get the total of 67,931,136.