21979215

素因数分解:

$3^3\times 5^1\times {\mathrm{17}}^1\times {\mathrm{61}}^1\times {\mathrm{157}}^1$

素因数の和:249

約数の個数: 64

約数和(自身を含む): 42318720

約数和(自身を除く): 20339505

約数列:

[1, 3, 5, 9, 15, 17, 27, 45, 51, 61, 85, 135, 153, 157, 183, 255, 305, 459, 471, 549, 765, 785, 915, 1037, 1413, 1647, 2295, 2355, 2669, 2745, 3111, 4239, 5185, 7065, 8007, 8235, 9333, 9577, 13345, 15555, 21195, 24021, 27999, 28731, 40035, 46665, 47885, 72063, 86193, 120105, 139995, 143655, 162809, 258579, 360315, 430965, 488427, 814045, 1292895, 1465281, 2442135, 4395843, 7326405, 21979215]

約数ペア:

[(1, 21979215), (3, 7326405), (5, 4395843), (9, 2442135), (15, 1465281), (17, 1292895), (27, 814045), (45, 488427), (51, 430965), (61, 360315), (85, 258579), (135, 162809), (153, 143655), (157, 139995), (183, 120105), (255, 86193), (305, 72063), (459, 47885), (471, 46665), (549, 40035), (765, 28731), (785, 27999), (915, 24021), (1037, 21195), (1413, 15555), (1647, 13345), (2295, 9577), (2355, 9333), (2669, 8235), (2745, 8007), (3111, 7065), (4239, 5185)]