21285760

素因数分解:

$2^7\times 5^1\times {\mathrm{79}}^1\times {\mathrm{421}}^1$

素因数の和:519

約数の個数: 64

約数和(自身を含む): 51652800

約数和(自身を除く): 30367040

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 79, 80, 128, 158, 160, 316, 320, 395, 421, 632, 640, 790, 842, 1264, 1580, 1684, 2105, 2528, 3160, 3368, 4210, 5056, 6320, 6736, 8420, 10112, 12640, 13472, 16840, 25280, 26944, 33259, 33680, 50560, 53888, 66518, 67360, 133036, 134720, 166295, 266072, 269440, 332590, 532144, 665180, 1064288, 1330360, 2128576, 2660720, 4257152, 5321440, 10642880, 21285760]

約数ペア:

[(1, 21285760), (2, 10642880), (4, 5321440), (5, 4257152), (8, 2660720), (10, 2128576), (16, 1330360), (20, 1064288), (32, 665180), (40, 532144), (64, 332590), (79, 269440), (80, 266072), (128, 166295), (158, 134720), (160, 133036), (316, 67360), (320, 66518), (395, 53888), (421, 50560), (632, 33680), (640, 33259), (790, 26944), (842, 25280), (1264, 16840), (1580, 13472), (1684, 12640), (2105, 10112), (2528, 8420), (3160, 6736), (3368, 6320), (4210, 5056)]