Compare 518 vs 521
| Property | 518 | 521 |
|---|---|---|
| Type | composite number | prime |
| Unique factors | 3 | 1 |
| Total factors | 3 | 1 |
| Prime factorization | 21 × 71 × 371 | 5211 |
| Prime factorization | 2 × 7 × 37 | 521 |
| Divisors count | 8 | 2 |
| Divisors | 1, 2, 7, 14, 37, 74, 259, 518 | 1, 521 |
| Number of properties | 0 | 6 |
| Chen primes | 70th | |
| Lucas primes | 8th | |
| Primes | 98th | |
| Pythagorean primes | 46th | |
| Solinas primes | 39th | |
| Twin primes (1st member) | 25th | |
| Roman numberals | DXVIII | DXXI |
| Base 2 | 10000001102 | 10000010012 |
| Base 3 | 2010123 | 2010223 |
| Base 4 | 200124 | 200214 |
| Base 5 | 40335 | 40415 |
| Base 6 | 22226 | 22256 |
| Base 7 | 13407 | 13437 |
| Base 8 | 10068 | 10118 |
| Base 9 | 6359 | 6389 |
| Base 10 | 51810 | 52110 |
| Base 11 | 43111 | 43411 |
| Base 12 | 37212 | 37512 |
| Base 13 | 30b13 | 31113 |
| Base 14 | 29014 | 29314 |
| Base 15 | 24815 | 24b15 |
| Base 16 | 20616 | 20916 |