21520520

素因数分解:

$2^3\times 5^1\times 7^1\times {\mathrm{151}}^1\times {\mathrm{509}}^1$

素因数の和:678

約数の個数: 64

約数和(自身を含む): 55814400

約数和(自身を除く): 34293880

約数列:

[1, 2, 4, 5, 7, 8, 10, 14, 20, 28, 35, 40, 56, 70, 140, 151, 280, 302, 509, 604, 755, 1018, 1057, 1208, 1510, 2036, 2114, 2545, 3020, 3563, 4072, 4228, 5090, 5285, 6040, 7126, 8456, 10180, 10570, 14252, 17815, 20360, 21140, 28504, 35630, 42280, 71260, 76859, 142520, 153718, 307436, 384295, 538013, 614872, 768590, 1076026, 1537180, 2152052, 2690065, 3074360, 4304104, 5380130, 10760260, 21520520]

約数ペア:

[(1, 21520520), (2, 10760260), (4, 5380130), (5, 4304104), (7, 3074360), (8, 2690065), (10, 2152052), (14, 1537180), (20, 1076026), (28, 768590), (35, 614872), (40, 538013), (56, 384295), (70, 307436), (140, 153718), (151, 142520), (280, 76859), (302, 71260), (509, 42280), (604, 35630), (755, 28504), (1018, 21140), (1057, 20360), (1208, 17815), (1510, 14252), (2036, 10570), (2114, 10180), (2545, 8456), (3020, 7126), (3563, 6040), (4072, 5285), (4228, 5090)]