21781420

素因数分解:

$2^2\times 5^1\times {\mathrm{17}}^1\times {\mathrm{64063}}^1$

素因数の和:64089

約数の個数: 24

約数和(自身を含む): 48432384

約数和(自身を除く): 26650964

約数列:

[1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340, 64063, 128126, 256252, 320315, 640630, 1089071, 1281260, 2178142, 4356284, 5445355, 10890710, 21781420]

約数ペア:

[(1, 21781420), (2, 10890710), (4, 5445355), (5, 4356284), (10, 2178142), (17, 1281260), (20, 1089071), (34, 640630), (68, 320315), (85, 256252), (170, 128126), (340, 64063)]