21020020

素因数分解:

$2^2\times 5^1\times 7^2\times {\mathrm{89}}^1\times {\mathrm{241}}^1$

素因数の和:353

約数の個数: 72

約数和(自身を含む): 52141320

約数和(自身を除く): 31121300

約数列:

[1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 49, 70, 89, 98, 140, 178, 196, 241, 245, 356, 445, 482, 490, 623, 890, 964, 980, 1205, 1246, 1687, 1780, 2410, 2492, 3115, 3374, 4361, 4820, 6230, 6748, 8435, 8722, 11809, 12460, 16870, 17444, 21449, 21805, 23618, 33740, 42898, 43610, 47236, 59045, 85796, 87220, 107245, 118090, 150143, 214490, 236180, 300286, 428980, 600572, 750715, 1051001, 1501430, 2102002, 3002860, 4204004, 5255005, 10510010, 21020020]

約数ペア:

[(1, 21020020), (2, 10510010), (4, 5255005), (5, 4204004), (7, 3002860), (10, 2102002), (14, 1501430), (20, 1051001), (28, 750715), (35, 600572), (49, 428980), (70, 300286), (89, 236180), (98, 214490), (140, 150143), (178, 118090), (196, 107245), (241, 87220), (245, 85796), (356, 59045), (445, 47236), (482, 43610), (490, 42898), (623, 33740), (890, 23618), (964, 21805), (980, 21449), (1205, 17444), (1246, 16870), (1687, 12460), (1780, 11809), (2410, 8722), (2492, 8435), (3115, 6748), (3374, 6230), (4361, 4820)]