138 (number)
From Freepedia
One hundred [and] thirty-eight (138) is the natural number following 137 but before 139.
| Cardinal | One hundred [and] thirty-four |
| Ordinal | 138th |
| Factorization | <math>2 \cdot 3 \cdot 23</math> |
| Divisors | 2, 3, 6, 23, 46, 69 |
| Roman numeral | CXXXVIII |
| Binary | 10001010 |
| Hexadecimal | 8A |
Contents |
In mathematics
Its factorization makes 138 a sphenic number. This number is the sum of four consecutive primes (29 + 31 + 37 + 41). It is the smallest product of 3 primes such that in base 10 the third prime is a concatenation of the other two.
138 is the third 47-gonal number.
138 is an Ulam number (Sloane's A002858).
It is also the number of stellations of the Triakis tetrahedron.
In science
In astronomy,
- The New General Catalogue object NGC138, a spiral galaxy in the constellation Pisces
- The Saros number of the solar eclipse series which began on 1472 June 6 and will end on 2716 July 11 The duration of Saros series 138 is 1244.0 years, and it contains 70 solar eclipses.
- The Saros number of the lunar eclipse series which began on 1503 October 5 and will end on 2982 March 30. The duration of Saros series 138 is 1442.4 years, and it contains 81 lunar eclipses.
In other fields
One hundred [and] thirty-eight is also:
- The episode number of The Simpsons "138th Episode Spectacular". Most other shows would have used a round number. This may be a reference to The Misfits usage of the number (see below)
- Occasionally used as a substitute for 1138 in George Lucas's oeuvre.
- The year AD 138 or 138 BC.
- Punk rock band The Misfits have a song titled "We Are 138" from their album Static Age. It is about the George Lucas film mentioned above. So the number 138 has great significance to all Misfits fans, many even adopting 'We Are One Thirty Eight' as a greeting amongst themselves
