21197781

素因数分解:

$3^4\times {\mathrm{11}}^1\times {\mathrm{37}}^1\times {\mathrm{643}}^1$

素因数の和:703

約数の個数: 40

約数和(自身を含む): 35533344

約数和(自身を除く): 14335563

約数列:

[1, 3, 9, 11, 27, 33, 37, 81, 99, 111, 297, 333, 407, 643, 891, 999, 1221, 1929, 2997, 3663, 5787, 7073, 10989, 17361, 21219, 23791, 32967, 52083, 63657, 71373, 190971, 214119, 261701, 572913, 642357, 785103, 1927071, 2355309, 7065927, 21197781]

約数ペア:

[(1, 21197781), (3, 7065927), (9, 2355309), (11, 1927071), (27, 785103), (33, 642357), (37, 572913), (81, 261701), (99, 214119), (111, 190971), (297, 71373), (333, 63657), (407, 52083), (643, 32967), (891, 23791), (999, 21219), (1221, 17361), (1929, 10989), (2997, 7073), (3663, 5787)]