Compare 145 vs 149
| Property | 145 | 149 |
|---|---|---|
| Type | semiprime | prime |
| Unique factors | 2 | 1 |
| Total factors | 2 | 1 |
| Prime factorization | 51 × 291 | 1491 |
| Prime factorization | 5 × 29 | 149 |
| Divisors count | 4 | 2 |
| Divisors | 1, 5, 29, 145 | 1, 149 |
| Number of properties | 1 | 8 |
| Chen primes | 29th | |
| Emirps | 11th | |
| Good primes | 14th | |
| Harmonic primes | 12th | |
| Long primes | 13th | |
| Primes | 35th | |
| Pythagorean primes | 16th | |
| Semiprimes | 49th | |
| Twin primes (1st member) | 12th | |
| Roman numberals | CXLV | CXLIX |
| Base 2 | 100100012 | 100101012 |
| Base 3 | 121013 | 121123 |
| Base 4 | 21014 | 21114 |
| Base 5 | 10405 | 10445 |
| Base 6 | 4016 | 4056 |
| Base 7 | 2657 | 3027 |
| Base 8 | 2218 | 2258 |
| Base 9 | 1719 | 1759 |
| Base 10 | 14510 | 14910 |
| Base 11 | 12211 | 12611 |
| Base 12 | 10112 | 10512 |
| Base 13 | b213 | b613 |
| Base 14 | a514 | a914 |
| Base 15 | 9a15 | 9e15 |
| Base 16 | 9116 | 9516 |