Compare 1981 vs 1989
| Property | 1981 | 1989 |
|---|---|---|
| Type | semiprime | composite number |
| Unique factors | 2 | 3 |
| Total factors | 2 | 4 |
| Prime factorization | 71 × 2831 | 32 × 131 × 171 |
| Prime factorization | 7 × 283 | 3 × 3 × 13 × 17 |
| Divisors count | 4 | 12 |
| Divisors | 1, 7, 283, 1981 | 1, 3, 9, 13, 17, 39, 51, 117, 153, 221, 663, 1989 |
| Number of properties | 1 | 0 |
| Semiprimes | 572nd | |
| Roman numberals | MCMLXXXI | MCMLXXXIX |
| Base 2 | 111101111012 | 111110001012 |
| Base 3 | 22011013 | 22012003 |
| Base 4 | 1323314 | 1330114 |
| Base 5 | 304115 | 304245 |
| Base 6 | 131016 | 131136 |
| Base 7 | 55307 | 55417 |
| Base 8 | 36758 | 37058 |
| Base 9 | 26419 | 26509 |
| Base 10 | 198110 | 198910 |
| Base 11 | 154111 | 154911 |
| Base 12 | 119112 | 119912 |
| Base 13 | b9513 | ba013 |
| Base 14 | a1714 | a2114 |
| Base 15 | 8c115 | 8c915 |
| Base 16 | 7bd16 | 7c516 |