Compare 991 vs 1553
| Property | 991 | 1553 |
|---|---|---|
| Type | prime | prime |
| Unique factors | 1 | 1 |
| Total factors | 1 | 1 |
| Prime factorization | 9911 | 15531 |
| Prime factorization | 991 | 1553 |
| Divisors count | 2 | 2 |
| Divisors | 1, 991 | 1, 1553 |
| Number of properties | 10 | 8 |
| Additive primes | 89th | |
| Chen primes | 115th | 156th |
| Cousin primes (2nd member) | 54th | |
| Emirps | 36th | |
| Isolated primes | 98th | 146th |
| Long primes | 94th | |
| Lucky primes | 42nd | |
| Primes | 167th | 245th |
| Pythagorean primes | 118th | |
| Sexy primes (1st member) | 74th | 107th |
| Solinas primes | 43rd | |
| Super primes | 39th | |
| Ulam primes | 18th | 23rd |
| Roman numberals | CMXCI | MDLIII |
| Base 2 | 11110111112 | 110000100012 |
| Base 3 | 11002013 | 20101123 |
| Base 4 | 331334 | 1201014 |
| Base 5 | 124315 | 222035 |
| Base 6 | 43316 | 111056 |
| Base 7 | 26147 | 43467 |
| Base 8 | 17378 | 30218 |
| Base 9 | 13219 | 21159 |
| Base 10 | 99110 | 155310 |
| Base 11 | 82111 | 119211 |
| Base 12 | 6a712 | a9512 |
| Base 13 | 5b313 | 92613 |
| Base 14 | 50b14 | 7cd14 |
| Base 15 | 46115 | 6d815 |
| Base 16 | 3df16 | 61116 |