Compare 991 vs 1087
| Property | 991 | 1087 |
|---|---|---|
| Type | prime | prime |
| Unique factors | 1 | 1 |
| Total factors | 1 | 1 |
| Prime factorization | 9911 | 10871 |
| Prime factorization | 991 | 1087 |
| Divisors count | 2 | 2 |
| Divisors | 1, 991 | 1, 1087 |
| Number of properties | 10 | 11 |
| Additive primes | 89th | |
| Chen primes | 115th | |
| Cousin primes (1st member) | 43rd | |
| Emirps | 36th | |
| Good primes | 47th | |
| Isolated primes | 98th | 104th |
| Kynea primes | 5th | |
| Long primes | 67th | |
| Lucky primes | 42nd | 47th |
| Primes | 167th | 181st |
| Prime triplets (1st member) | 31st | |
| Sexy primes (1st member) | 74th | 78th |
| Solinas primes | 43rd | 50th |
| Super primes | 39th | 42nd |
| Ulam primes | 18th | |
| Roman numberals | CMXCI | MLXXXVII |
| Base 2 | 11110111112 | 100001111112 |
| Base 3 | 11002013 | 11110213 |
| Base 4 | 331334 | 1003334 |
| Base 5 | 124315 | 133225 |
| Base 6 | 43316 | 50116 |
| Base 7 | 26147 | 31127 |
| Base 8 | 17378 | 20778 |
| Base 9 | 13219 | 14379 |
| Base 10 | 99110 | 108710 |
| Base 11 | 82111 | 8a911 |
| Base 12 | 6a712 | 76712 |
| Base 13 | 5b313 | 65813 |
| Base 14 | 50b14 | 57914 |
| Base 15 | 46115 | 4c715 |
| Base 16 | 3df16 | 43f16 |