21320720

素因数分解:

$2^4\times 5^1\times {\mathrm{17}}^1\times {\mathrm{61}}^1\times {\mathrm{257}}^1$

素因数の和:348

約数の個数: 80

約数和(自身を含む): 53554608

約数和(自身を除く): 32233888

約数列:

[1, 2, 4, 5, 8, 10, 16, 17, 20, 34, 40, 61, 68, 80, 85, 122, 136, 170, 244, 257, 272, 305, 340, 488, 514, 610, 680, 976, 1028, 1037, 1220, 1285, 1360, 2056, 2074, 2440, 2570, 4112, 4148, 4369, 4880, 5140, 5185, 8296, 8738, 10280, 10370, 15677, 16592, 17476, 20560, 20740, 21845, 31354, 34952, 41480, 43690, 62708, 69904, 78385, 82960, 87380, 125416, 156770, 174760, 250832, 266509, 313540, 349520, 533018, 627080, 1066036, 1254160, 1332545, 2132072, 2665090, 4264144, 5330180, 10660360, 21320720]

約数ペア:

[(1, 21320720), (2, 10660360), (4, 5330180), (5, 4264144), (8, 2665090), (10, 2132072), (16, 1332545), (17, 1254160), (20, 1066036), (34, 627080), (40, 533018), (61, 349520), (68, 313540), (80, 266509), (85, 250832), (122, 174760), (136, 156770), (170, 125416), (244, 87380), (257, 82960), (272, 78385), (305, 69904), (340, 62708), (488, 43690), (514, 41480), (610, 34952), (680, 31354), (976, 21845), (1028, 20740), (1037, 20560), (1220, 17476), (1285, 16592), (1360, 15677), (2056, 10370), (2074, 10280), (2440, 8738), (2570, 8296), (4112, 5185), (4148, 5140), (4369, 4880)]