# 29 (number)

29 (twenty-nine) is the natural number following 28 and preceding 30.

 ← 28 29 30 →
Cardinaltwenty-nine
Ordinal29th
(twenty-ninth)
Factorizationprime
Prime10th
Divisors1, 29
Greek numeralΚΘ´
Roman numeralXXIX
Binary111012
Ternary10023
Quaternary1314
Quinary1045
Senary456
Octal358
Duodecimal2512
Vigesimal1920
Base 36T36

## Mathematics

It is the tenth prime number, and also the fourth primorial prime. It forms a twin prime pair with thirty-one, which is also a primorial prime. Twenty-nine is also the sixth Sophie Germain prime. It is also the sum of three consecutive squares, 22 + 32 + 42. It is a Lucas prime, a Pell prime, and a tetranacci number. It is an Eisenstein prime with no imaginary part and real part of the form 3n − 1. 29 is also the 10th supersingular prime.

None of the first 29 natural numbers have more than two different prime factors. This is the longest such consecutive sequence.

29 is a Markov number, appearing in the solutions to x2 + y2 + z2 = 3xyz: {2, 5, 29}, {2, 29, 169}, {5, 29, 433}, {29, 169, 14701}, etc.

29 is a Perrin number, preceded in the sequence by 12, 17, 22.

29 is the smallest positive whole number that cannot be made from the numbers {1, 2, 3, 4}, using each exactly once and using only addition, subtraction, multiplication, and division.

## Religion

• The Bishnois community follows 29 principles. Guru Jambheshwar had laid down 29 principles to be followed by the sect in 1485 A.D. In Hindi, Bish means 20 and noi means 9; thus, Bishnoi translates as Twenty-niners.
• The number of suras in the Qur'an that begin with muqatta'at