21581721

素因数分解:

$3^4\times 7^1\times {\mathrm{17}}^1\times {\mathrm{2239}}^1$

素因数の和:2275

約数の個数: 40

約数和(自身を含む): 39029760

約数和(自身を除く): 17448039

約数列:

[1, 3, 7, 9, 17, 21, 27, 51, 63, 81, 119, 153, 189, 357, 459, 567, 1071, 1377, 2239, 3213, 6717, 9639, 15673, 20151, 38063, 47019, 60453, 114189, 141057, 181359, 266441, 342567, 423171, 799323, 1027701, 1269513, 2397969, 3083103, 7193907, 21581721]

約数ペア:

[(1, 21581721), (3, 7193907), (7, 3083103), (9, 2397969), (17, 1269513), (21, 1027701), (27, 799323), (51, 423171), (63, 342567), (81, 266441), (119, 181359), (153, 141057), (189, 114189), (357, 60453), (459, 47019), (567, 38063), (1071, 20151), (1377, 15673), (2239, 9639), (3213, 6717)]