Compare 21989 vs 21991
| Property | 21989 | 21991 |
|---|---|---|
| Type | semiprime | prime |
| Unique factors | 2 | 1 |
| Total factors | 2 | 1 |
| Prime factorization | 111 × 19991 | 219911 |
| Prime factorization | 11 × 1999 | 21991 |
| Divisors count | 4 | 2 |
| Divisors | 1, 11, 1999, 21989 | 1, 21991 |
| Number of properties | 1 | 5 |
| Chen primes | 1208th | |
| Isolated primes | 1720th | |
| Primes | 2463rd | |
| Semiprimes | 5552nd | |
| Sexy primes (1st member) | 742nd | |
| Sexy prime triplets (1st member) | 202nd | |
| Roman numberals | ||
| Base 2 | 1010101111001012 | 1010101111001112 |
| Base 3 | 10100111023 | 10100111113 |
| Base 4 | 111132114 | 111132134 |
| Base 5 | 12004245 | 12004315 |
| Base 6 | 2454456 | 2454516 |
| Base 7 | 1210527 | 1210547 |
| Base 8 | 527458 | 527478 |
| Base 9 | 331429 | 331449 |
| Base 10 | 2198910 | 2199110 |
| Base 11 | 1558011 | 1558211 |
| Base 12 | 1088512 | 1088712 |
| Base 13 | a01613 | a01813 |
| Base 14 | 802914 | 802b14 |
| Base 15 | 67ae15 | 67b115 |
| Base 16 | 55e516 | 55e716 |