Compare 21 vs 39
| Property | 21 | 39 |
|---|---|---|
| Type | semiprime | semiprime |
| Unique factors | 2 | 2 |
| Total factors | 2 | 2 |
| Prime factorization | 31 × 71 | 31 × 131 |
| Prime factorization | 3 × 7 | 3 × 13 |
| Divisors count | 4 | 4 |
| Divisors | 1, 3, 7, 21 | 1, 3, 13, 39 |
| Number of properties | 1 | 1 |
| Semiprimes | 7th | 15th |
| Roman numberals | XXI | XXXIX |
| Base 2 | 101012 | 1001112 |
| Base 3 | 2103 | 11103 |
| Base 4 | 1114 | 2134 |
| Base 5 | 415 | 1245 |
| Base 6 | 336 | 1036 |
| Base 7 | 307 | 547 |
| Base 8 | 258 | 478 |
| Base 9 | 239 | 439 |
| Base 10 | 2110 | 3910 |
| Base 11 | 1a11 | 3611 |
| Base 12 | 1912 | 3312 |
| Base 13 | 1813 | 3013 |
| Base 14 | 1714 | 2b14 |
| Base 15 | 1615 | 2915 |
| Base 16 | 1516 | 2716 |