Compare 661 vs 683
| Property | 661 | 683 |
|---|---|---|
| Type | prime | prime |
| Unique factors | 1 | 1 |
| Total factors | 1 | 1 |
| Prime factorization | 6611 | 6831 |
| Prime factorization | 661 | 683 |
| Divisors count | 2 | 2 |
| Divisors | 1, 661 | 1, 683 |
| Number of properties | 5 | 10 |
| Additive primes | 65th | 66th |
| Centered decagonal primes | 8th | |
| Chen primes | 86th | |
| Happy primes | 28th | |
| Harmonic primes | 49th | |
| Isolated primes | 65th | |
| Left-truncatable primes | 42nd | |
| Primes | 121st | 124th |
| Pythagorean primes | 57th | |
| Sexy primes (2nd member) | 60th | |
| Sophie germain primes | 31st | |
| Twin primes (2nd member) | 30th | |
| Wagstaff primes | 4th | |
| Roman numberals | DCLXI | DCLXXXIII |
| Base 2 | 10100101012 | 10101010112 |
| Base 3 | 2201113 | 2210223 |
| Base 4 | 221114 | 222234 |
| Base 5 | 101215 | 102135 |
| Base 6 | 30216 | 30556 |
| Base 7 | 16337 | 16647 |
| Base 8 | 12258 | 12538 |
| Base 9 | 8149 | 8389 |
| Base 10 | 66110 | 68310 |
| Base 11 | 55111 | 57111 |
| Base 12 | 47112 | 48b12 |
| Base 13 | 3bb13 | 40713 |
| Base 14 | 35314 | 36b14 |
| Base 15 | 2e115 | 30815 |
| Base 16 | 29516 | 2ab16 |