Compare 643 vs 644
| Property | 643 | 644 |
|---|---|---|
| Type | prime | composite number |
| Unique factors | 1 | 3 |
| Total factors | 1 | 4 |
| Prime factorization | 6431 | 22 × 71 × 231 |
| Prime factorization | 643 | 2 × 2 × 7 × 23 |
| Divisors count | 2 | 12 |
| Divisors | 1, 643 | 1, 2, 4, 7, 14, 23, 28, 46, 92, 161, 322, 644 |
| Number of properties | 7 | 0 |
| 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 | DCXLIII | DCXLIV |
| Base 2 | 10100000112 | 10100001002 |
| Base 3 | 2122113 | 2122123 |
| Base 4 | 220034 | 220104 |
| Base 5 | 100335 | 100345 |
| Base 6 | 25516 | 25526 |
| Base 7 | 16067 | 16107 |
| Base 8 | 12038 | 12048 |
| Base 9 | 7849 | 7859 |
| Base 10 | 64310 | 64410 |
| Base 11 | 53511 | 53611 |
| Base 12 | 45712 | 45812 |
| Base 13 | 3a613 | 3a713 |
| Base 14 | 33d14 | 34014 |
| Base 15 | 2cd15 | 2ce15 |
| Base 16 | 28316 | 28416 |