900000020

素因数分解:

$2^2\times 5^1\times {\mathrm{41}}^1\times {\mathrm{347}}^1\times {\mathrm{3163}}^1$

素因数の和:3560

約数の個数: 48

約数和(自身を含む): 1942291008

約数和(自身を除く): 1042290988

約数列:

[1, 2, 4, 5, 10, 20, 41, 82, 164, 205, 347, 410, 694, 820, 1388, 1735, 3163, 3470, 6326, 6940, 12652, 14227, 15815, 28454, 31630, 56908, 63260, 71135, 129683, 142270, 259366, 284540, 518732, 648415, 1097561, 1296830, 2195122, 2593660, 4390244, 5487805, 10975610, 21951220, 45000001, 90000002, 180000004, 225000005, 450000010, 900000020]

約数ペア:

[(1, 900000020), (2, 450000010), (4, 225000005), (5, 180000004), (10, 90000002), (20, 45000001), (41, 21951220), (82, 10975610), (164, 5487805), (205, 4390244), (347, 2593660), (410, 2195122), (694, 1296830), (820, 1097561), (1388, 648415), (1735, 518732), (3163, 284540), (3470, 259366), (6326, 142270), (6940, 129683), (12652, 71135), (14227, 63260), (15815, 56908), (28454, 31630)]