21581720

素因数分解:

$2^3\times 5^1\times {\mathrm{19}}^1\times {\mathrm{73}}^1\times {\mathrm{389}}^1$

素因数の和:492

約数の個数: 64

約数和(自身を含む): 51948000

約数和(自身を除く): 30366280

約数列:

[1, 2, 4, 5, 8, 10, 19, 20, 38, 40, 73, 76, 95, 146, 152, 190, 292, 365, 380, 389, 584, 730, 760, 778, 1387, 1460, 1556, 1945, 2774, 2920, 3112, 3890, 5548, 6935, 7391, 7780, 11096, 13870, 14782, 15560, 27740, 28397, 29564, 36955, 55480, 56794, 59128, 73910, 113588, 141985, 147820, 227176, 283970, 295640, 539543, 567940, 1079086, 1135880, 2158172, 2697715, 4316344, 5395430, 10790860, 21581720]

約数ペア:

[(1, 21581720), (2, 10790860), (4, 5395430), (5, 4316344), (8, 2697715), (10, 2158172), (19, 1135880), (20, 1079086), (38, 567940), (40, 539543), (73, 295640), (76, 283970), (95, 227176), (146, 147820), (152, 141985), (190, 113588), (292, 73910), (365, 59128), (380, 56794), (389, 55480), (584, 36955), (730, 29564), (760, 28397), (778, 27740), (1387, 15560), (1460, 14782), (1556, 13870), (1945, 11096), (2774, 7780), (2920, 7391), (3112, 6935), (3890, 5548)]