20787921

素因数分解:

$3^5\times 7^1\times {\mathrm{11}}^2\times {\mathrm{101}}^1$

素因数の和:145

約数の個数: 72

約数和(自身を含む): 39504192

約数和(自身を除く): 18716271

約数列:

[1, 3, 7, 9, 11, 21, 27, 33, 63, 77, 81, 99, 101, 121, 189, 231, 243, 297, 303, 363, 567, 693, 707, 847, 891, 909, 1089, 1111, 1701, 2079, 2121, 2541, 2673, 2727, 3267, 3333, 6237, 6363, 7623, 7777, 8181, 9801, 9999, 12221, 18711, 19089, 22869, 23331, 24543, 29403, 29997, 36663, 57267, 68607, 69993, 85547, 89991, 109989, 171801, 205821, 209979, 256641, 269973, 329967, 629937, 769923, 989901, 1889811, 2309769, 2969703, 6929307, 20787921]

約数ペア:

[(1, 20787921), (3, 6929307), (7, 2969703), (9, 2309769), (11, 1889811), (21, 989901), (27, 769923), (33, 629937), (63, 329967), (77, 269973), (81, 256641), (99, 209979), (101, 205821), (121, 171801), (189, 109989), (231, 89991), (243, 85547), (297, 69993), (303, 68607), (363, 57267), (567, 36663), (693, 29997), (707, 29403), (847, 24543), (891, 23331), (909, 22869), (1089, 19089), (1111, 18711), (1701, 12221), (2079, 9999), (2121, 9801), (2541, 8181), (2673, 7777), (2727, 7623), (3267, 6363), (3333, 6237)]