21409960

素因数分解:

$2^3\times 5^1\times {\mathrm{11}}^1\times {\mathrm{13}}^1\times {\mathrm{19}}^1\times {\mathrm{197}}^1$

素因数の和:251

約数の個数: 128

約数和(自身を含む): 59875200

約数和(自身を除く): 38465240

約数列:

[1, 2, 4, 5, 8, 10, 11, 13, 19, 20, 22, 26, 38, 40, 44, 52, 55, 65, 76, 88, 95, 104, 110, 130, 143, 152, 190, 197, 209, 220, 247, 260, 286, 380, 394, 418, 440, 494, 520, 572, 715, 760, 788, 836, 985, 988, 1045, 1144, 1235, 1430, 1576, 1672, 1970, 1976, 2090, 2167, 2470, 2561, 2717, 2860, 3743, 3940, 4180, 4334, 4940, 5122, 5434, 5720, 7486, 7880, 8360, 8668, 9880, 10244, 10835, 10868, 12805, 13585, 14972, 17336, 18715, 20488, 21670, 21736, 25610, 27170, 28171, 29944, 37430, 41173, 43340, 48659, 51220, 54340, 56342, 74860, 82346, 86680, 97318, 102440, 108680, 112684, 140855, 149720, 164692, 194636, 205865, 225368, 243295, 281710, 329384, 389272, 411730, 486590, 535249, 563420, 823460, 973180, 1070498, 1126840, 1646920, 1946360, 2140996, 2676245, 4281992, 5352490, 10704980, 21409960]

約数ペア:

[(1, 21409960), (2, 10704980), (4, 5352490), (5, 4281992), (8, 2676245), (10, 2140996), (11, 1946360), (13, 1646920), (19, 1126840), (20, 1070498), (22, 973180), (26, 823460), (38, 563420), (40, 535249), (44, 486590), (52, 411730), (55, 389272), (65, 329384), (76, 281710), (88, 243295), (95, 225368), (104, 205865), (110, 194636), (130, 164692), (143, 149720), (152, 140855), (190, 112684), (197, 108680), (209, 102440), (220, 97318), (247, 86680), (260, 82346), (286, 74860), (380, 56342), (394, 54340), (418, 51220), (440, 48659), (494, 43340), (520, 41173), (572, 37430), (715, 29944), (760, 28171), (788, 27170), (836, 25610), (985, 21736), (988, 21670), (1045, 20488), (1144, 18715), (1235, 17336), (1430, 14972), (1576, 13585), (1672, 12805), (1970, 10868), (1976, 10835), (2090, 10244), (2167, 9880), (2470, 8668), (2561, 8360), (2717, 7880), (2860, 7486), (3743, 5720), (3940, 5434), (4180, 5122), (4334, 4940)]