21780320

素因数分解:

$2^5\times 5^1\times {\mathrm{197}}^1\times {\mathrm{691}}^1$

素因数の和:903

約数の個数: 48

約数和(自身を含む): 51792048

約数和(自身を除く): 30011728

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 80, 160, 197, 394, 691, 788, 985, 1382, 1576, 1970, 2764, 3152, 3455, 3940, 5528, 6304, 6910, 7880, 11056, 13820, 15760, 22112, 27640, 31520, 55280, 110560, 136127, 272254, 544508, 680635, 1089016, 1361270, 2178032, 2722540, 4356064, 5445080, 10890160, 21780320]

約数ペア:

[(1, 21780320), (2, 10890160), (4, 5445080), (5, 4356064), (8, 2722540), (10, 2178032), (16, 1361270), (20, 1089016), (32, 680635), (40, 544508), (80, 272254), (160, 136127), (197, 110560), (394, 55280), (691, 31520), (788, 27640), (985, 22112), (1382, 15760), (1576, 13820), (1970, 11056), (2764, 7880), (3152, 6910), (3455, 6304), (3940, 5528)]