21720855

素因数分解:

$3^1\times 5^1\times {\mathrm{13}}^1\times {\mathrm{23}}^1\times {\mathrm{29}}^1\times {\mathrm{167}}^1$

素因数の和:240

約数の個数: 64

約数和(自身を含む): 40642560

約数和(自身を除く): 18921705

約数列:

[1, 3, 5, 13, 15, 23, 29, 39, 65, 69, 87, 115, 145, 167, 195, 299, 345, 377, 435, 501, 667, 835, 897, 1131, 1495, 1885, 2001, 2171, 2505, 3335, 3841, 4485, 4843, 5655, 6513, 8671, 10005, 10855, 11523, 14529, 19205, 24215, 26013, 32565, 43355, 49933, 57615, 62959, 72645, 111389, 130065, 149799, 188877, 249665, 314795, 334167, 556945, 748995, 944385, 1448057, 1670835, 4344171, 7240285, 21720855]

約数ペア:

[(1, 21720855), (3, 7240285), (5, 4344171), (13, 1670835), (15, 1448057), (23, 944385), (29, 748995), (39, 556945), (65, 334167), (69, 314795), (87, 249665), (115, 188877), (145, 149799), (167, 130065), (195, 111389), (299, 72645), (345, 62959), (377, 57615), (435, 49933), (501, 43355), (667, 32565), (835, 26013), (897, 24215), (1131, 19205), (1495, 14529), (1885, 11523), (2001, 10855), (2171, 10005), (2505, 8671), (3335, 6513), (3841, 5655), (4485, 4843)]