20991440

素因数分解:

$2^4\times 5^1\times {\mathrm{131}}^1\times {\mathrm{2003}}^1$

素因数の和:2147

約数の個数: 40

約数和(自身を含む): 49202208

約数和(自身を除く): 28210768

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 131, 262, 524, 655, 1048, 1310, 2003, 2096, 2620, 4006, 5240, 8012, 10015, 10480, 16024, 20030, 32048, 40060, 80120, 160240, 262393, 524786, 1049572, 1311965, 2099144, 2623930, 4198288, 5247860, 10495720, 20991440]

約数ペア:

[(1, 20991440), (2, 10495720), (4, 5247860), (5, 4198288), (8, 2623930), (10, 2099144), (16, 1311965), (20, 1049572), (40, 524786), (80, 262393), (131, 160240), (262, 80120), (524, 40060), (655, 32048), (1048, 20030), (1310, 16024), (2003, 10480), (2096, 10015), (2620, 8012), (4006, 5240)]