20781640

素因数分解:

$2^3\times 5^1\times {\mathrm{11}}^1\times {\mathrm{73}}^1\times {\mathrm{647}}^1$

素因数の和:742

約数の個数: 64

約数和(自身を含む): 51788160

約数和(自身を除く): 31006520

約数列:

[1, 2, 4, 5, 8, 10, 11, 20, 22, 40, 44, 55, 73, 88, 110, 146, 220, 292, 365, 440, 584, 647, 730, 803, 1294, 1460, 1606, 2588, 2920, 3212, 3235, 4015, 5176, 6424, 6470, 7117, 8030, 12940, 14234, 16060, 25880, 28468, 32120, 35585, 47231, 56936, 71170, 94462, 142340, 188924, 236155, 284680, 377848, 472310, 519541, 944620, 1039082, 1889240, 2078164, 2597705, 4156328, 5195410, 10390820, 20781640]

約数ペア:

[(1, 20781640), (2, 10390820), (4, 5195410), (5, 4156328), (8, 2597705), (10, 2078164), (11, 1889240), (20, 1039082), (22, 944620), (40, 519541), (44, 472310), (55, 377848), (73, 284680), (88, 236155), (110, 188924), (146, 142340), (220, 94462), (292, 71170), (365, 56936), (440, 47231), (584, 35585), (647, 32120), (730, 28468), (803, 25880), (1294, 16060), (1460, 14234), (1606, 12940), (2588, 8030), (2920, 7117), (3212, 6470), (3235, 6424), (4015, 5176)]