21009681

素因数分解:

$3^2\times 7^2\times {\mathrm{11}}^1\times {\mathrm{61}}^1\times {\mathrm{71}}^1$

素因数の和:163

約数の個数: 72

約数和(自身を含む): 39693888

約数和(自身を除く): 18684207

約数列:

[1, 3, 7, 9, 11, 21, 33, 49, 61, 63, 71, 77, 99, 147, 183, 213, 231, 427, 441, 497, 539, 549, 639, 671, 693, 781, 1281, 1491, 1617, 2013, 2343, 2989, 3479, 3843, 4331, 4473, 4697, 4851, 5467, 6039, 7029, 8967, 10437, 12993, 14091, 16401, 26901, 30317, 31311, 32879, 38269, 38979, 42273, 47641, 49203, 90951, 98637, 114807, 142923, 212219, 272853, 295911, 333487, 344421, 428769, 636657, 1000461, 1909971, 2334409, 3001383, 7003227, 21009681]

約数ペア:

[(1, 21009681), (3, 7003227), (7, 3001383), (9, 2334409), (11, 1909971), (21, 1000461), (33, 636657), (49, 428769), (61, 344421), (63, 333487), (71, 295911), (77, 272853), (99, 212219), (147, 142923), (183, 114807), (213, 98637), (231, 90951), (427, 49203), (441, 47641), (497, 42273), (539, 38979), (549, 38269), (639, 32879), (671, 31311), (693, 30317), (781, 26901), (1281, 16401), (1491, 14091), (1617, 12993), (2013, 10437), (2343, 8967), (2989, 7029), (3479, 6039), (3843, 5467), (4331, 4851), (4473, 4697)]