19988991

素因数分解:

$3^3\times {\mathrm{11}}^1\times {\mathrm{17}}^1\times {\mathrm{37}}^1\times {\mathrm{107}}^1$

素因数の和:181

約数の個数: 64

約数和(自身を含む): 35458560

約数和(自身を除く): 15469569

約数列:

[1, 3, 9, 11, 17, 27, 33, 37, 51, 99, 107, 111, 153, 187, 297, 321, 333, 407, 459, 561, 629, 963, 999, 1177, 1221, 1683, 1819, 1887, 2889, 3531, 3663, 3959, 5049, 5457, 5661, 6919, 10593, 10989, 11877, 16371, 16983, 20009, 20757, 31779, 35631, 43549, 49113, 60027, 62271, 67303, 106893, 130647, 180081, 186813, 201909, 391941, 540243, 605727, 740333, 1175823, 1817181, 2220999, 6662997, 19988991]

約数ペア:

[(1, 19988991), (3, 6662997), (9, 2220999), (11, 1817181), (17, 1175823), (27, 740333), (33, 605727), (37, 540243), (51, 391941), (99, 201909), (107, 186813), (111, 180081), (153, 130647), (187, 106893), (297, 67303), (321, 62271), (333, 60027), (407, 49113), (459, 43549), (561, 35631), (629, 31779), (963, 20757), (999, 20009), (1177, 16983), (1221, 16371), (1683, 11877), (1819, 10989), (1887, 10593), (2889, 6919), (3531, 5661), (3663, 5457), (3959, 5049)]