129 (number)
From Wikipedia, the free encyclopedia
129 is the natural number following 128 and preceding 130.
| Cardinal | One hundred [and] twenty-nine |
| Ordinal | 129th |
| Factorization |  |
| Roman numeral | CXXIX |
| Binary | 10000001 |
| Hexadecimal | 81 |
[edit] In mathematics
129 is the sum of the first ten prime numbers. It is the smallest number that can be expressed as a sum of three squares in four different ways: 112 + 22 + 22 and 102 + 52 + 22 and 82 + 82 + 12 and 82 + 72 + 42.
129 is a repdigit in base 6 (333).
[edit] In other fields
One hundred [and] twenty-nine is also:
- The designation of a spur route of Interstate 29 in Sioux City, Iowa.
- The year AD 129 or 129 BC.
This page discusses the number 129. For the year, see 129.
