21005840

素因数分解:

$2^4\times 5^1\times {\mathrm{67}}^1\times {\mathrm{3919}}^1$

素因数の和:3999

約数の個数: 40

約数和(自身を含む): 49580160

約数和(自身を除く): 28574320

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 40, 67, 80, 134, 268, 335, 536, 670, 1072, 1340, 2680, 3919, 5360, 7838, 15676, 19595, 31352, 39190, 62704, 78380, 156760, 262573, 313520, 525146, 1050292, 1312865, 2100584, 2625730, 4201168, 5251460, 10502920, 21005840]

約数ペア:

[(1, 21005840), (2, 10502920), (4, 5251460), (5, 4201168), (8, 2625730), (10, 2100584), (16, 1312865), (20, 1050292), (40, 525146), (67, 313520), (80, 262573), (134, 156760), (268, 78380), (335, 62704), (536, 39190), (670, 31352), (1072, 19595), (1340, 15676), (2680, 7838), (3919, 5360)]