21205665

素因数分解:

$3^3\times 5^1\times {\mathrm{13}}^1\times {\mathrm{43}}^1\times {\mathrm{281}}^1$

素因数の和:351

約数の個数: 64

約数和(自身を含む): 41690880

約数和(自身を除く): 20485215

約数列:

[1, 3, 5, 9, 13, 15, 27, 39, 43, 45, 65, 117, 129, 135, 195, 215, 281, 351, 387, 559, 585, 645, 843, 1161, 1405, 1677, 1755, 1935, 2529, 2795, 3653, 4215, 5031, 5805, 7587, 8385, 10959, 12083, 12645, 15093, 18265, 25155, 32877, 36249, 37935, 54795, 60415, 75465, 98631, 108747, 157079, 164385, 181245, 326241, 471237, 493155, 543735, 785395, 1413711, 1631205, 2356185, 4241133, 7068555, 21205665]

約数ペア:

[(1, 21205665), (3, 7068555), (5, 4241133), (9, 2356185), (13, 1631205), (15, 1413711), (27, 785395), (39, 543735), (43, 493155), (45, 471237), (65, 326241), (117, 181245), (129, 164385), (135, 157079), (195, 108747), (215, 98631), (281, 75465), (351, 60415), (387, 54795), (559, 37935), (585, 36249), (645, 32877), (843, 25155), (1161, 18265), (1405, 15093), (1677, 12645), (1755, 12083), (1935, 10959), (2529, 8385), (2795, 7587), (3653, 5805), (4215, 5031)]