1729 (number)
| 
 | ||||
|---|---|---|---|---|
| Cardinal | one thousand seven hundred twenty-nine | |||
| Ordinal | 1729th (one thousand seven hundred twenty-ninth) | |||
| Factorization | 7 × 13 × 19 | |||
| Divisors | 1, 7, 13, 19, 91, 133, 247, 1729 | |||
| Greek numeral | ,ΑΨΚΘ´ | |||
| Roman numeral | MDCCXXIX, mdccxxix | |||
| Binary | 110110000012 | |||
| Ternary | 21010013 | |||
| Senary | 120016 | |||
| Octal | 33018 | |||
| Duodecimal | 100112 | |||
| Hexadecimal | 6C116 | |||
1729 is the natural number following 1728 and preceding 1730. It is the first nontrivial taxicab number, expressed as the sum of two cubic positive integers in two different ways. It is known as the Ramanujan number or Hardy–Ramanujan number after G. H. Hardy and Srinivasa Ramanujan.