21278803

素因数分解:

$7^1\times {\mathrm{13}}^1\times {\mathrm{19}}^1\times {\mathrm{31}}^1\times {\mathrm{397}}^1$

素因数の和:467

約数の個数: 32

約数和(自身を含む): 28528640

約数和(自身を除く): 7249837

約数列:

[1, 7, 13, 19, 31, 91, 133, 217, 247, 397, 403, 589, 1729, 2779, 2821, 4123, 5161, 7543, 7657, 12307, 36127, 52801, 53599, 86149, 98059, 159991, 233833, 686413, 1119937, 1636831, 3039829, 21278803]

約数ペア:

[(1, 21278803), (7, 3039829), (13, 1636831), (19, 1119937), (31, 686413), (91, 233833), (133, 159991), (217, 98059), (247, 86149), (397, 53599), (403, 52801), (589, 36127), (1729, 12307), (2779, 7657), (2821, 7543), (4123, 5161)]