Compare 1781 vs 1789
| Property | 1781 | 1789 |
|---|---|---|
| Type | semiprime | prime |
| Unique factors | 2 | 1 |
| Total factors | 2 | 1 |
| Prime factorization | 131 × 1371 | 17891 |
| Prime factorization | 13 × 137 | 1789 |
| Divisors count | 4 | 2 |
| Divisors | 1, 13, 137, 1781 | 1, 1789 |
| Number of properties | 1 | 8 |
| Emirps | 86th | |
| Long primes | 108th | |
| Primes | 278th | |
| Prime triplets (3rd member) | 45th | |
| Pythagorean primes | 135th | |
| Semiprimes | 514th | |
| Sexy primes (2nd member) | 119th | |
| Sexy prime triplets (3rd member) | 46th | |
| Twin primes (2nd member) | 56th | |
| Roman numberals | MDCCLXXXI | MDCCLXXXIX |
| Base 2 | 110111101012 | 110111111012 |
| Base 3 | 21022223 | 21100213 |
| Base 4 | 1233114 | 1233314 |
| Base 5 | 241115 | 241245 |
| Base 6 | 121256 | 121416 |
| Base 7 | 51237 | 51347 |
| Base 8 | 33658 | 33758 |
| Base 9 | 23889 | 24079 |
| Base 10 | 178110 | 178910 |
| Base 11 | 137a11 | 138711 |
| Base 12 | 104512 | 105112 |
| Base 13 | a7013 | a7813 |
| Base 14 | 91314 | 91b14 |
| Base 15 | 7db15 | 7e415 |
| Base 16 | 6f516 | 6fd16 |