21147775

素因数分解:

$5^2\times {\mathrm{11}}^2\times {\mathrm{6991}}^1$

素因数の和:7023

約数の個数: 18

約数和(自身を含む): 28828016

約数和(自身を除く): 7680241

約数列:

[1, 5, 11, 25, 55, 121, 275, 605, 3025, 6991, 34955, 76901, 174775, 384505, 845911, 1922525, 4229555, 21147775]

約数ペア:

[(1, 21147775), (5, 4229555), (11, 1922525), (25, 845911), (55, 384505), (121, 174775), (275, 76901), (605, 34955), (3025, 6991)]