Compare 81 vs 87
| Property | 81 | 87 |
|---|---|---|
| Type | composite number | semiprime |
| Unique factors | 1 | 2 |
| Total factors | 4 | 2 |
| Prime factorization | 34 | 31 × 291 |
| Prime factorization | 3 × 3 × 3 × 3 | 3 × 29 |
| Divisors count | 5 | 4 |
| Divisors | 1, 3, 9, 27, 81 | 1, 3, 29, 87 |
| Number of properties | 0 | 1 |
| Semiprimes | 30th | |
| Roman numberals | LXXXI | LXXXVII |
| Base 2 | 10100012 | 10101112 |
| Base 3 | 100003 | 100203 |
| Base 4 | 11014 | 11134 |
| Base 5 | 3115 | 3225 |
| Base 6 | 2136 | 2236 |
| Base 7 | 1447 | 1537 |
| Base 8 | 1218 | 1278 |
| Base 9 | 1009 | 1069 |
| Base 10 | 8110 | 8710 |
| Base 11 | 7411 | 7a11 |
| Base 12 | 6912 | 7312 |
| Base 13 | 6313 | 6913 |
| Base 14 | 5b14 | 6314 |
| Base 15 | 5615 | 5c15 |
| Base 16 | 5116 | 5716 |