Compare 9 vs 51
| Property | 9 | 51 | 
|---|---|---|
| Type | semiprime | semiprime | 
| Unique factors | 1 | 2 | 
| Total factors | 2 | 2 | 
| Prime factorization | 32 | 31 × 171 | 
| Prime factorization | 3 × 3 | 3 × 17 | 
| Divisors count | 3 | 4 | 
| Divisors | 1, 3, 9 | 1, 3, 17, 51 | 
| Number of properties | 1 | 1 | 
| Semiprimes | 3rd | 18th | 
| Roman numberals | IX | LI | 
| Base 2 | 10012 | 1100112 | 
| Base 3 | 1003 | 12203 | 
| Base 4 | 214 | 3034 | 
| Base 5 | 145 | 2015 | 
| Base 6 | 136 | 1236 | 
| Base 7 | 127 | 1027 | 
| Base 8 | 118 | 638 | 
| Base 9 | 109 | 569 | 
| Base 10 | 910 | 5110 | 
| Base 11 | 911 | 4711 | 
| Base 12 | 912 | 4312 | 
| Base 13 | 913 | 3c13 | 
| Base 14 | 914 | 3914 | 
| Base 15 | 915 | 3615 | 
| Base 16 | 916 | 3316 |