81440000

素因数分解:

$2^8\times 5^4\times {\mathrm{509}}^1$

素因数の和:545

約数の個数: 90

約数和(自身を含む): 203536410

約数和(自身を除く): 122096410

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 25, 32, 40, 50, 64, 80, 100, 125, 128, 160, 200, 250, 256, 320, 400, 500, 509, 625, 640, 800, 1000, 1018, 1250, 1280, 1600, 2000, 2036, 2500, 2545, 3200, 4000, 4072, 5000, 5090, 6400, 8000, 8144, 10000, 10180, 12725, 16000, 16288, 20000, 20360, 25450, 32000, 32576, 40000, 40720, 50900, 63625, 65152, 80000, 81440, 101800, 127250, 130304, 160000, 162880, 203600, 254500, 318125, 325760, 407200, 509000, 636250, 651520, 814400, 1018000, 1272500, 1628800, 2036000, 2545000, 3257600, 4072000, 5090000, 8144000, 10180000, 16288000, 20360000, 40720000, 81440000]

約数ペア:

[(1, 81440000), (2, 40720000), (4, 20360000), (5, 16288000), (8, 10180000), (10, 8144000), (16, 5090000), (20, 4072000), (25, 3257600), (32, 2545000), (40, 2036000), (50, 1628800), (64, 1272500), (80, 1018000), (100, 814400), (125, 651520), (128, 636250), (160, 509000), (200, 407200), (250, 325760), (256, 318125), (320, 254500), (400, 203600), (500, 162880), (509, 160000), (625, 130304), (640, 127250), (800, 101800), (1000, 81440), (1018, 80000), (1250, 65152), (1280, 63625), (1600, 50900), (2000, 40720), (2036, 40000), (2500, 32576), (2545, 32000), (3200, 25450), (4000, 20360), (4072, 20000), (5000, 16288), (5090, 16000), (6400, 12725), (8000, 10180), (8144, 10000)]