21278691

素因数分解:

$3^2\times 7^3\times {\mathrm{61}}^1\times {\mathrm{113}}^1$

素因数の和:201

約数の個数: 48

約数和(自身を含む): 36753600

約数和(自身を除く): 15474909

約数列:

[1, 3, 7, 9, 21, 49, 61, 63, 113, 147, 183, 339, 343, 427, 441, 549, 791, 1017, 1029, 1281, 2373, 2989, 3087, 3843, 5537, 6893, 7119, 8967, 16611, 20679, 20923, 26901, 38759, 48251, 49833, 62037, 62769, 116277, 144753, 188307, 337757, 348831, 434259, 1013271, 2364299, 3039813, 7092897, 21278691]

約数ペア:

[(1, 21278691), (3, 7092897), (7, 3039813), (9, 2364299), (21, 1013271), (49, 434259), (61, 348831), (63, 337757), (113, 188307), (147, 144753), (183, 116277), (339, 62769), (343, 62037), (427, 49833), (441, 48251), (549, 38759), (791, 26901), (1017, 20923), (1029, 20679), (1281, 16611), (2373, 8967), (2989, 7119), (3087, 6893), (3843, 5537)]