21720560

素因数分解:

$2^4\times 5^1\times {\mathrm{17}}^1\times {\mathrm{15971}}^1$

素因数の和:16001

約数の個数: 40

約数和(自身を含む): 53474256

約数和(自身を除く): 31753696

約数列:

[1, 2, 4, 5, 8, 10, 16, 17, 20, 34, 40, 68, 80, 85, 136, 170, 272, 340, 680, 1360, 15971, 31942, 63884, 79855, 127768, 159710, 255536, 271507, 319420, 543014, 638840, 1086028, 1277680, 1357535, 2172056, 2715070, 4344112, 5430140, 10860280, 21720560]

約数ペア:

[(1, 21720560), (2, 10860280), (4, 5430140), (5, 4344112), (8, 2715070), (10, 2172056), (16, 1357535), (17, 1277680), (20, 1086028), (34, 638840), (40, 543014), (68, 319420), (80, 271507), (85, 255536), (136, 159710), (170, 127768), (272, 79855), (340, 63884), (680, 31942), (1360, 15971)]