21978640

素因数分解:

$2^4\times 5^1\times {\mathrm{257}}^1\times {\mathrm{1069}}^1$

素因数の和:1339

約数の個数: 40

約数和(自身を含む): 51347160

約数和(自身を除く): 29368520

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 257, 514, 1028, 1069, 1285, 2056, 2138, 2570, 4112, 4276, 5140, 5345, 8552, 10280, 10690, 17104, 20560, 21380, 42760, 85520, 274733, 549466, 1098932, 1373665, 2197864, 2747330, 4395728, 5494660, 10989320, 21978640]

約数ペア:

[(1, 21978640), (2, 10989320), (4, 5494660), (5, 4395728), (8, 2747330), (10, 2197864), (16, 1373665), (20, 1098932), (40, 549466), (80, 274733), (257, 85520), (514, 42760), (1028, 21380), (1069, 20560), (1285, 17104), (2056, 10690), (2138, 10280), (2570, 8552), (4112, 5345), (4276, 5140)]