21203980

素因数分解:

$2^2\times 5^1\times 7^1\times {\mathrm{311}}^1\times {\mathrm{487}}^1$

素因数の和:814

約数の個数: 48

約数和(自身を含む): 51158016

約数和(自身を除く): 29954036

約数列:

[1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 70, 140, 311, 487, 622, 974, 1244, 1555, 1948, 2177, 2435, 3110, 3409, 4354, 4870, 6220, 6818, 8708, 9740, 10885, 13636, 17045, 21770, 34090, 43540, 68180, 151457, 302914, 605828, 757285, 1060199, 1514570, 2120398, 3029140, 4240796, 5300995, 10601990, 21203980]

約数ペア:

[(1, 21203980), (2, 10601990), (4, 5300995), (5, 4240796), (7, 3029140), (10, 2120398), (14, 1514570), (20, 1060199), (28, 757285), (35, 605828), (70, 302914), (140, 151457), (311, 68180), (487, 43540), (622, 34090), (974, 21770), (1244, 17045), (1555, 13636), (1948, 10885), (2177, 9740), (2435, 8708), (3110, 6818), (3409, 6220), (4354, 4870)]