21389680

素因数分解:

$2^4\times 5^1\times {\mathrm{13}}^1\times {\mathrm{131}}^1\times {\mathrm{157}}^1$

素因数の和:314

約数の個数: 80

約数和(自身を含む): 54309024

約数和(自身を除く): 32919344

約数列:

[1, 2, 4, 5, 8, 10, 13, 16, 20, 26, 40, 52, 65, 80, 104, 130, 131, 157, 208, 260, 262, 314, 520, 524, 628, 655, 785, 1040, 1048, 1256, 1310, 1570, 1703, 2041, 2096, 2512, 2620, 3140, 3406, 4082, 5240, 6280, 6812, 8164, 8515, 10205, 10480, 12560, 13624, 16328, 17030, 20410, 20567, 27248, 32656, 34060, 40820, 41134, 68120, 81640, 82268, 102835, 136240, 163280, 164536, 205670, 267371, 329072, 411340, 534742, 822680, 1069484, 1336855, 1645360, 2138968, 2673710, 4277936, 5347420, 10694840, 21389680]

約数ペア:

[(1, 21389680), (2, 10694840), (4, 5347420), (5, 4277936), (8, 2673710), (10, 2138968), (13, 1645360), (16, 1336855), (20, 1069484), (26, 822680), (40, 534742), (52, 411340), (65, 329072), (80, 267371), (104, 205670), (130, 164536), (131, 163280), (157, 136240), (208, 102835), (260, 82268), (262, 81640), (314, 68120), (520, 41134), (524, 40820), (628, 34060), (655, 32656), (785, 27248), (1040, 20567), (1048, 20410), (1256, 17030), (1310, 16328), (1570, 13624), (1703, 12560), (2041, 10480), (2096, 10205), (2512, 8515), (2620, 8164), (3140, 6812), (3406, 6280), (4082, 5240)]