Compare 661 vs 709
| Property | 661 | 709 |
|---|---|---|
| Type | prime | prime |
| Unique factors | 1 | 1 |
| Total factors | 1 | 1 |
| Prime factorization | 6611 | 7091 |
| Prime factorization | 661 | 709 |
| Divisors count | 2 | 2 |
| Divisors | 1, 661 | 1, 709 |
| Number of properties | 5 | 8 |
| Additive primes | 65th | |
| Centered decagonal primes | 8th | |
| Emirps | 22nd | |
| Happy primes | 29th | |
| Harmonic primes | 51st | |
| Isolated primes | 68th | |
| Long primes | 46th | |
| Primes | 121st | 127th |
| Pythagorean primes | 57th | 61st |
| Super primes | 31st | |
| Twin primes (2nd member) | 30th | |
| Roman numberals | DCLXI | DCCIX |
| Base 2 | 10100101012 | 10110001012 |
| Base 3 | 2201113 | 2220213 |
| Base 4 | 221114 | 230114 |
| Base 5 | 101215 | 103145 |
| Base 6 | 30216 | 31416 |
| Base 7 | 16337 | 20327 |
| Base 8 | 12258 | 13058 |
| Base 9 | 8149 | 8679 |
| Base 10 | 66110 | 70910 |
| Base 11 | 55111 | 59511 |
| Base 12 | 47112 | 4b112 |
| Base 13 | 3bb13 | 42713 |
| Base 14 | 35314 | 38914 |
| Base 15 | 2e115 | 32415 |
| Base 16 | 29516 | 2c516 |