The factors of the number 263,360,640 are: 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 20, 24, 30, 32, 40, 48, 60, 64, 73, 80, 96, 120, 128, 146, 160, 192, 219, 240, 292, 320, 365, 384, 438, 480, 584, 640, 730, 876, 960, 1095, 1168, 1460, 1752, 1879, 1920, 2190, 2336, 2920, 3504, 3758, 4380, 4672, 5637, 5840, 7008, 7516, 8760, 9344, 9395, 11274, 11680, 14016, 15032, 17520, 18790, 22548, 23360, 28032, 28185, 30064, 35040, 37580, 45096, 46720, 56370, 60128, 70080, 75160, 90192, 112740, 120256, 137167, 140160, 150320, 180384, 225480, 240512, 274334, 300640, 360768, 411501, 450960, 548668, 601280, 685835, 721536, 823002, 901920, 1097336, 1202560, 1371670, 1646004, 1803840, 2057505, 2194672, 2743340, 3292008, 3607680, 4115010, 4389344, 5486680, 6584016, 8230020, 8778688, 10973360, 13168032, 16460040, 17557376, 21946720, 26336064, 32920080, 43893440, 52672128, 65840160, 87786880, 131680320, 263360640.
If you add them up, you will get the total of 851,414,400.