Compare 638 vs 643
| Property | 638 | 643 |
|---|---|---|
| Type | composite number | prime |
| Unique factors | 3 | 1 |
| Total factors | 3 | 1 |
| Prime factorization | 21 × 111 × 291 | 6431 |
| Prime factorization | 2 × 11 × 29 | 643 |
| Divisors count | 8 | 2 |
| Divisors | 1, 2, 11, 22, 29, 58, 319, 638 | 1, 643 |
| Number of properties | 0 | 7 |
| Additive primes | 63rd | |
| Cousin primes (1st member) | 29th | |
| Left-truncatable primes | 38th | |
| Lucky primes | 33rd | |
| Primes | 117th | |
| Prime triplets (2nd member) | 24th | |
| Twin primes (2nd member) | 29th | |
| Roman numberals | DCXXXVIII | DCXLIII |
| Base 2 | 10011111102 | 10100000112 |
| Base 3 | 2121223 | 2122113 |
| Base 4 | 213324 | 220034 |
| Base 5 | 100235 | 100335 |
| Base 6 | 25426 | 25516 |
| Base 7 | 16017 | 16067 |
| Base 8 | 11768 | 12038 |
| Base 9 | 7789 | 7849 |
| Base 10 | 63810 | 64310 |
| Base 11 | 53011 | 53511 |
| Base 12 | 45212 | 45712 |
| Base 13 | 3a113 | 3a613 |
| Base 14 | 33814 | 33d14 |
| Base 15 | 2c815 | 2cd15 |
| Base 16 | 27e16 | 28316 |