109 is the natural number

Natural number

In mathematics, the natural numbers are the ordinary whole numbers used for counting and ordering . These purposes are related to the linguistic notions of cardinal and ordinal numbers, respectively...

 following 108

108 (number)

108 is the natural number following 107 and preceding 109.- In mathematics :One hundred [and] eight is an abundant number and a semiperfect number...

 and preceding 110

110 (number)

110 is the natural number following 109 and preceding 111.It is also known as "eleventy", a term made famous by linguist and author J. R. R...

.

In mathematics

One hundred [and] nine is the 29th prime number

Prime number

A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself. A natural number greater than 1 that is not a prime number is called a composite number. For example 5 is prime, as only 1 and 5 divide it, whereas 6 is composite, since it has the divisors 2...

, and also a Chen prime

Chen prime

A prime number p is called a Chen prime if p + 2 is either a prime or a product of two primes. The even number 2p + 2 therefore satisfies Chen's theorem....

. The previous prime is 107

107 (number)

107 is the natural number following 106 and preceding 108.-In mathematics:One hundred [and] seven is the 28th prime number. The next prime is 109, with which it comprises a twin prime, making 107 a Chen prime....

, making them both twin prime

Twin prime

A twin prime is a prime number that differs from another prime number by two. Except for the pair , this is the smallest possible difference between two primes. Some examples of twin prime pairs are , , , , and...

s. 109 is a centered triangular number

Centered triangular number

A centered triangular number is a centered figurate number that represents a triangle with a dot in the center and all other dots surrounding the center in successive triangular layers...

.

109 is the smallest factor

Divisor

In mathematics, a divisor of an integer n, also called a factor of n, is an integer which divides n without leaving a remainder.-Explanation:...

 of one more than the product of the first twenty-three terms of the Euclid–Mullin sequence, making it the twenty-fourth term.

109 is the smallest number which is palindromic in bases 5 and 9.

The cycle of the decimal equivalent of 1/109 ends ...853211, the first six Fibonacci number

Fibonacci number

In mathematics, the Fibonacci numbers are the numbers in the following integer sequence:0,\;1,\;1,\;2,\;3,\;5,\;8,\;13,\;21,\;34,\;55,\;89,\;144,\; \ldots\; ....

s in reversed order.