21387645

素因数分解:

$3^5\times 5^1\times {\mathrm{29}}^1\times {\mathrm{607}}^1$

素因数の和:656

約数の個数: 48

約数和(自身を含む): 39836160

約数和(自身を除く): 18448515

約数列:

[1, 3, 5, 9, 15, 27, 29, 45, 81, 87, 135, 145, 243, 261, 405, 435, 607, 783, 1215, 1305, 1821, 2349, 3035, 3915, 5463, 7047, 9105, 11745, 16389, 17603, 27315, 35235, 49167, 52809, 81945, 88015, 147501, 158427, 245835, 264045, 475281, 737505, 792135, 1425843, 2376405, 4277529, 7129215, 21387645]

約数ペア:

[(1, 21387645), (3, 7129215), (5, 4277529), (9, 2376405), (15, 1425843), (27, 792135), (29, 737505), (45, 475281), (81, 264045), (87, 245835), (135, 158427), (145, 147501), (243, 88015), (261, 81945), (405, 52809), (435, 49167), (607, 35235), (783, 27315), (1215, 17603), (1305, 16389), (1821, 11745), (2349, 9105), (3035, 7047), (3915, 5463)]