21408520

素因数分解:

$2^3\times 5^1\times 7^1\times {\mathrm{157}}^1\times {\mathrm{487}}^1$

素因数の和:662

約数の個数: 64

約数和(自身を含む): 55514880

約数和(自身を除く): 34106360

約数列:

[1, 2, 4, 5, 7, 8, 10, 14, 20, 28, 35, 40, 56, 70, 140, 157, 280, 314, 487, 628, 785, 974, 1099, 1256, 1570, 1948, 2198, 2435, 3140, 3409, 3896, 4396, 4870, 5495, 6280, 6818, 8792, 9740, 10990, 13636, 17045, 19480, 21980, 27272, 34090, 43960, 68180, 76459, 136360, 152918, 305836, 382295, 535213, 611672, 764590, 1070426, 1529180, 2140852, 2676065, 3058360, 4281704, 5352130, 10704260, 21408520]

約数ペア:

[(1, 21408520), (2, 10704260), (4, 5352130), (5, 4281704), (7, 3058360), (8, 2676065), (10, 2140852), (14, 1529180), (20, 1070426), (28, 764590), (35, 611672), (40, 535213), (56, 382295), (70, 305836), (140, 152918), (157, 136360), (280, 76459), (314, 68180), (487, 43960), (628, 34090), (785, 27272), (974, 21980), (1099, 19480), (1256, 17045), (1570, 13636), (1948, 10990), (2198, 9740), (2435, 8792), (3140, 6818), (3409, 6280), (3896, 5495), (4396, 4870)]