21080720

素因数分解:

$2^4\times 5^1\times {\mathrm{101}}^1\times {\mathrm{2609}}^1$

素因数の和:2723

約数の個数: 40

約数和(自身を含む): 49516920

約数和(自身を除く): 28436200

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 101, 202, 404, 505, 808, 1010, 1616, 2020, 2609, 4040, 5218, 8080, 10436, 13045, 20872, 26090, 41744, 52180, 104360, 208720, 263509, 527018, 1054036, 1317545, 2108072, 2635090, 4216144, 5270180, 10540360, 21080720]

約数ペア:

[(1, 21080720), (2, 10540360), (4, 5270180), (5, 4216144), (8, 2635090), (10, 2108072), (16, 1317545), (20, 1054036), (40, 527018), (80, 263509), (101, 208720), (202, 104360), (404, 52180), (505, 41744), (808, 26090), (1010, 20872), (1616, 13045), (2020, 10436), (2609, 8080), (4040, 5218)]