21009989

素因数分解:

$7^1\times {\mathrm{11}}^1\times {\mathrm{13}}^1\times {\mathrm{139}}^1\times {\mathrm{151}}^1$

素因数の和:321

約数の個数: 32

約数和(自身を含む): 28600320

約数和(自身を除く): 7590331

約数列:

[1, 7, 11, 13, 77, 91, 139, 143, 151, 973, 1001, 1057, 1529, 1661, 1807, 1963, 10703, 11627, 12649, 13741, 19877, 20989, 21593, 139139, 146923, 151151, 230879, 272857, 1616153, 1909999, 3001427, 21009989]

約数ペア:

[(1, 21009989), (7, 3001427), (11, 1909999), (13, 1616153), (77, 272857), (91, 230879), (139, 151151), (143, 146923), (151, 139139), (973, 21593), (1001, 20989), (1057, 19877), (1529, 13741), (1661, 12649), (1807, 11627), (1963, 10703)]