39 (number)
39 is the natural number following 38 and preceding 40.
| |||
| Cardinal | thirty-nine | ||
| Ordinal | 39th (thirty-ninth) | ||
| Factorization | |||
| Roman numeral | XXXIX | ||
| Binary | 100111 | ||
| Hexadecimal | 27 | ||
In mathematics
Thirty-nine is the sum of five consecutive primes (3 + 5 + 7 + 11 + 13) and the sum of the first three powers of 3 (). Given 39, the Mertens function returns 0.
In other fields
Thirty-nine is also:
- The atomic number of yttrium.
- In the title of the John Buchan, novel The Thirty-Nine Steps.
- The code for international direct-dialed phone calls to Italy.
- I-39 is the designation for a US interstate highway from Normal, Illinois to Wausau, Wisconsin.
- The eternal age of comedian Jack Benny, and many other people as they grow older.
- The year A.D. 39, 39 BC, or 1939.
- Japanase internet chat slang for "thank you" when written with numbers.