19870221

素因数分解:

$3^1\times 7^1\times {\mathrm{37}}^1\times {\mathrm{107}}^1\times {\mathrm{239}}^1$

素因数の和:393

約数の個数: 32

約数和(自身を含む): 31518720

約数和(自身を除く): 11648499

約数列:

[1, 3, 7, 21, 37, 107, 111, 239, 259, 321, 717, 749, 777, 1673, 2247, 3959, 5019, 8843, 11877, 25573, 26529, 27713, 61901, 76719, 83139, 179011, 185703, 537033, 946201, 2838603, 6623407, 19870221]

約数ペア:

[(1, 19870221), (3, 6623407), (7, 2838603), (21, 946201), (37, 537033), (107, 185703), (111, 179011), (239, 83139), (259, 76719), (321, 61901), (717, 27713), (749, 26529), (777, 25573), (1673, 11877), (2247, 8843), (3959, 5019)]