Compare 20991 vs 21001
| Property | 20991 | 21001 |
|---|---|---|
| Type | semiprime | prime |
| Unique factors | 2 | 1 |
| Total factors | 2 | 1 |
| Prime factorization | 31 × 69971 | 210011 |
| Prime factorization | 3 × 6997 | 21001 |
| Divisors count | 4 | 2 |
| Divisors | 1, 3, 6997, 20991 | 1, 21001 |
| Number of properties | 1 | 5 |
| Chen primes | 1162nd | |
| Harmonic primes | 867th | |
| Isolated primes | 1648th | |
| Primes | 2361st | |
| Pythagorean primes | 1173rd | |
| Semiprimes | 5325th | |
| Roman numberals | ||
| Base 2 | 1010001111111112 | 1010010000010012 |
| Base 3 | 10012101103 | 10012102113 |
| Base 4 | 110133334 | 110200214 |
| Base 5 | 11324315 | 11330015 |
| Base 6 | 2411036 | 2411216 |
| Base 7 | 1151257 | 1151417 |
| Base 8 | 507778 | 510118 |
| Base 9 | 317139 | 317249 |
| Base 10 | 2099110 | 2100110 |
| Base 11 | 1485311 | 1486211 |
| Base 12 | 1019312 | 101a112 |
| Base 13 | 972913 | 973613 |
| Base 14 | 791514 | 792114 |
| Base 15 | 634615 | 635115 |
| Base 16 | 51ff16 | 520916 |