21400820

素因数分解:

$2^2\times 5^1\times 7^1\times {\mathrm{71}}^1\times {\mathrm{2153}}^1$

素因数の和:2240

約数の個数: 48

約数和(自身を含む): 52109568

約数和(自身を除く): 30708748

約数列:

[1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 70, 71, 140, 142, 284, 355, 497, 710, 994, 1420, 1988, 2153, 2485, 4306, 4970, 8612, 9940, 10765, 15071, 21530, 30142, 43060, 60284, 75355, 150710, 152863, 301420, 305726, 611452, 764315, 1070041, 1528630, 2140082, 3057260, 4280164, 5350205, 10700410, 21400820]

約数ペア:

[(1, 21400820), (2, 10700410), (4, 5350205), (5, 4280164), (7, 3057260), (10, 2140082), (14, 1528630), (20, 1070041), (28, 764315), (35, 611452), (70, 305726), (71, 301420), (140, 152863), (142, 150710), (284, 75355), (355, 60284), (497, 43060), (710, 30142), (994, 21530), (1420, 15071), (1988, 10765), (2153, 9940), (2485, 8612), (4306, 4970)]