The factors of the number 15,251,544 are: 1, 2, 3, 4, 6, 7, 8, 9, 11, 12, 14, 18, 21, 22, 24, 27, 28, 33, 36, 42, 44, 49, 54, 56, 63, 66, 72, 77, 84, 88, 98, 99, 108, 126, 131, 132, 147, 154, 168, 189, 196, 198, 216, 231, 252, 262, 264, 294, 297, 308, 378, 392, 393, 396, 441, 462, 504, 524, 539, 588, 594, 616, 693, 756, 786, 792, 882, 917, 924, 1048, 1078, 1176, 1179, 1188, 1323, 1386, 1441, 1512, 1572, 1617, 1764, 1834, 1848, 2079, 2156, 2358, 2376, 2646, 2751, 2772, 2882, 3144, 3234, 3528, 3537, 3668, 4158, 4312, 4323, 4716, 4851, 5292, 5502, 5544, 5764, 6419, 6468, 7074, 7336, 8253, 8316, 8646, 9432, 9702, 10087, 10584, 11004, 11528, 12838, 12936, 12969, 14148, 14553, 16506, 16632, 17292, 19257, 19404, 20174, 22008, 24759, 25676, 25938, 28296, 29106, 30261, 33012, 34584, 38514, 38808, 38907, 40348, 49518, 51352, 51876, 57771, 58212, 60522, 66024, 70609, 77028, 77814, 80696, 90783, 99036, 103752, 115542, 116424, 121044, 141218, 154056, 155628, 173313, 181566, 198072, 211827, 231084, 242088, 272349, 282436, 311256, 346626, 363132, 423654, 462168, 544698, 564872, 635481, 693252, 726264, 847308, 1089396, 1270962, 1386504, 1694616, 1906443, 2178792, 2541924, 3812886, 5083848, 7625772, 15251544.
If you add them up, you will get the total of 54,172,800.