39 (number)
From Freepedia
| Cardinal | thirty-nine |
| Ordinal | 39th (thirty-ninth) |
| Factorization | <math>3\cdot 13</math> |
| Roman numeral | XXXIX |
| Binary | 100111 |
| Hexadecimal | 27 |
39 is the natural number following 38 and preceding 40.
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 (<math>3^1 + 3^2 + 3^3</math>). Given 39, the Mertens function returns 0.
In astronomy
- Messier object M39, a magnitude 5.5 open cluster in the constellation Cygnus
- The New General Catalogue object NGC 39, a spiral galaxy in the constellation Andromeda
- The Saros number of the
- solar eclipse series which began on -1718 May 26 and ended on -438 July 3. The duration of Saros series 39 was 1280.1 years, and it contained 72 solar eclipses.
- lunar eclipse series which began on -1380 March 26 and ended on -82 May 14. The duration of Saros series 39 was 1298.1 years, and it contained 73 lunar eclipses.
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 traditional number of times citizens of Ancient Rome hit their slaves when beating them, referred to as "Forty save one."
- Japanese Internet chat slang for "thank you" when written with numbers.
- The year A.D. 39, 39 BC, or 1939.
- '39 is also a track on Queen's album A Night At the Opera. Interestingly, if one numbers the tracks on Queen's original studio albums in sequential order starting with their first, '39 does in fact fall in the thirty-ninth position.
