19980500

素因数分解:

$2^2\times 5^3\times {\mathrm{89}}^1\times {\mathrm{449}}^1$

素因数の和:557

約数の個数: 48

約数和(自身を含む): 44226000

約数和(自身を除く): 24245500

約数列:

[1, 2, 4, 5, 10, 20, 25, 50, 89, 100, 125, 178, 250, 356, 445, 449, 500, 890, 898, 1780, 1796, 2225, 2245, 4450, 4490, 8900, 8980, 11125, 11225, 22250, 22450, 39961, 44500, 44900, 56125, 79922, 112250, 159844, 199805, 224500, 399610, 799220, 999025, 1998050, 3996100, 4995125, 9990250, 19980500]

約数ペア:

[(1, 19980500), (2, 9990250), (4, 4995125), (5, 3996100), (10, 1998050), (20, 999025), (25, 799220), (50, 399610), (89, 224500), (100, 199805), (125, 159844), (178, 112250), (250, 79922), (356, 56125), (445, 44900), (449, 44500), (500, 39961), (890, 22450), (898, 22250), (1780, 11225), (1796, 11125), (2225, 8980), (2245, 8900), (4450, 4490)]