Compare 1815 vs 1821
| Property | 1815 | 1821 |
|---|---|---|
| Type | composite number | semiprime |
| Unique factors | 3 | 2 |
| Total factors | 4 | 2 |
| Prime factorization | 31 × 51 × 112 | 31 × 6071 |
| Prime factorization | 3 × 5 × 11 × 11 | 3 × 607 |
| Divisors count | 12 | 4 |
| Divisors | 1, 3, 5, 11, 15, 33, 55, 121, 165, 363, 605, 1815 | 1, 3, 607, 1821 |
| Number of properties | 0 | 1 |
| Semiprimes | 524th | |
| Roman numberals | MDCCCXV | MDCCCXXI |
| Base 2 | 111000101112 | 111000111012 |
| Base 3 | 21110203 | 21111103 |
| Base 4 | 1301134 | 1301314 |
| Base 5 | 242305 | 242415 |
| Base 6 | 122236 | 122336 |
| Base 7 | 52027 | 52117 |
| Base 8 | 34278 | 34358 |
| Base 9 | 24369 | 24439 |
| Base 10 | 181510 | 182110 |
| Base 11 | 140011 | 140611 |
| Base 12 | 107312 | 107912 |
| Base 13 | a9813 | aa113 |
| Base 14 | 93914 | 94114 |
| Base 15 | 81015 | 81615 |
| Base 16 | 71716 | 71d16 |