21638421

素因数分解:

$3^5\times 7^1\times {\mathrm{12721}}^1$

素因数の和:12743

約数の個数: 24

約数和(自身を含む): 37046464

約数和(自身を除く): 15408043

約数列:

[1, 3, 7, 9, 21, 27, 63, 81, 189, 243, 567, 1701, 12721, 38163, 89047, 114489, 267141, 343467, 801423, 1030401, 2404269, 3091203, 7212807, 21638421]

約数ペア:

[(1, 21638421), (3, 7212807), (7, 3091203), (9, 2404269), (21, 1030401), (27, 801423), (63, 343467), (81, 267141), (189, 114489), (243, 89047), (567, 38163), (1701, 12721)]