Main Page | See live article | Alphabetical index Twenty-nine (29, XXIX) is the natural number following twenty-eight and preceding thirty. It is the tenth prime number, and also a primorial prime, the next prime number as well as primoral prime being thirty-one, with which it comprises a twin prime. Twenty-nine is also the sum of three squares, 22 + 32 + 42. It is a Lucas number and a Pell number. The lunar month is very close to twenty-nine days. Twenty-nine is also The atomic number of copper. The number of days February has on leap years. The number of letters in the Finnish and Norwegian alphabets. The designation of Interstate 29, a freeway that runs from Missouri to North Dakota. In the name of the town Twentynine Palms, California, also the name of the adjoining Marine Corps base, affectionately referred to by Marines as "Twentynine Stumps". See also: twenty-seven, twenty-eight, thirty, thirty-one, integer, list of numbers. This article is about the number. For the year AD 29, see 29. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.