Compare 28 vs 61
| Property | 28 | 61 |
|---|---|---|
| Type | composite number | prime |
| Unique factors | 2 | 1 |
| Total factors | 3 | 1 |
| Prime factorization | 22 × 71 | 611 |
| Prime factorization | 2 × 2 × 7 | 61 |
| Divisors count | 6 | 2 |
| Divisors | 1, 2, 4, 7, 14, 28 | 1, 61 |
| Number of properties | 0 | 12 |
| Additive primes | 11th | |
| Centered decagonal primes | 3rd | |
| Centered square primes | 4th | |
| Cuban primes 1 | 4th | |
| Long primes | 8th | |
| Primes | 18th | |
| Pythagorean primes | 8th | |
| Sexy primes (1st member) | 12th | |
| Sexy prime quadrupletss (1st member) | 4th | |
| Sexy prime triplets (1st member) | 8th | |
| Solinas primes | 15th | |
| Twin primes (2nd member) | 7th | |
| Roman numberals | XXVIII | LXI |
| Base 2 | 111002 | 1111012 |
| Base 3 | 10013 | 20213 |
| Base 4 | 1304 | 3314 |
| Base 5 | 1035 | 2215 |
| Base 6 | 446 | 1416 |
| Base 7 | 407 | 1157 |
| Base 8 | 348 | 758 |
| Base 9 | 319 | 679 |
| Base 10 | 2810 | 6110 |
| Base 11 | 2611 | 5611 |
| Base 12 | 2412 | 5112 |
| Base 13 | 2213 | 4913 |
| Base 14 | 2014 | 4514 |
| Base 15 | 1d15 | 4115 |
| Base 16 | 1c16 | 3d16 |