Compare 1981 vs 2018
| Property | 1981 | 2018 |
|---|---|---|
| Type | semiprime | semiprime |
| Unique factors | 2 | 2 |
| Total factors | 2 | 2 |
| Prime factorization | 71 × 2831 | 21 × 10091 |
| Prime factorization | 7 × 283 | 2 × 1009 |
| Divisors count | 4 | 4 |
| Divisors | 1, 7, 283, 1981 | 1, 2, 1009, 2018 |
| Number of properties | 1 | 1 |
| Semiprimes | 572nd | 579th |
| Roman numberals | MCMLXXXI | MMXVIII |
| Base 2 | 111101111012 | 111111000102 |
| Base 3 | 22011013 | 22022023 |
| Base 4 | 1323314 | 1332024 |
| Base 5 | 304115 | 310335 |
| Base 6 | 131016 | 132026 |
| Base 7 | 55307 | 56127 |
| Base 8 | 36758 | 37428 |
| Base 9 | 26419 | 26829 |
| Base 10 | 198110 | 201810 |
| Base 11 | 154111 | 157511 |
| Base 12 | 119112 | 120212 |
| Base 13 | b9513 | bc313 |
| Base 14 | a1714 | a4214 |
| Base 15 | 8c115 | 8e815 |
| Base 16 | 7bd16 | 7e216 |