81918440

素因数分解:

$2^3\times 5^1\times {\mathrm{43}}^1\times {\mathrm{97}}^1\times {\mathrm{491}}^1$

素因数の和:642

約数の個数: 64

約数和(自身を含む): 190935360

約数和(自身を除く): 109016920

約数列:

[1, 2, 4, 5, 8, 10, 20, 40, 43, 86, 97, 172, 194, 215, 344, 388, 430, 485, 491, 776, 860, 970, 982, 1720, 1940, 1964, 2455, 3880, 3928, 4171, 4910, 8342, 9820, 16684, 19640, 20855, 21113, 33368, 41710, 42226, 47627, 83420, 84452, 95254, 105565, 166840, 168904, 190508, 211130, 238135, 381016, 422260, 476270, 844520, 952540, 1905080, 2047961, 4095922, 8191844, 10239805, 16383688, 20479610, 40959220, 81918440]

約数ペア:

[(1, 81918440), (2, 40959220), (4, 20479610), (5, 16383688), (8, 10239805), (10, 8191844), (20, 4095922), (40, 2047961), (43, 1905080), (86, 952540), (97, 844520), (172, 476270), (194, 422260), (215, 381016), (344, 238135), (388, 211130), (430, 190508), (485, 168904), (491, 166840), (776, 105565), (860, 95254), (970, 84452), (982, 83420), (1720, 47627), (1940, 42226), (1964, 41710), (2455, 33368), (3880, 21113), (3928, 20855), (4171, 19640), (4910, 16684), (8342, 9820)]