9 (number)

9 (nine) is the natural number following 8 and preceding 10.

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Nine is a composite number, its proper divisors being 1 and 3. It is 3 times 3 and hence the third square number. 9 is a Motzkin number.

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In base 10 a number is evenly divisible by nine if and only if the iterative sum of its digits reduces to 9. A simple way of saying this is that if you multiply nine by any whole number, and repeatedly add the digits of the answer until it's just one digit, you will end up with nine:

Natural number: Natural number can mean either a positive integer (, , , , ...) or a non-negative integer (, , , , , ...)....

8:   This article is about the year 8. For other uses of 8, see 8 (number)....

Composite number: A composite number is a positive integer which has a positive divisor other than one or itself. By definition, every integer greater than one is either a prime number or a composite number. The numbers zero and one are considered to be neither prime nor composite. The integer 14 is a composite numbe...

9 (number) related Images and Photos (experimental)

Number 8 1949	Number 36	Number 23	Number 25
Number 23 (BD)	Number 18 1950	ABBA: Number Ones CD	ABBA: Number Ones CD
Number 23, The (DVD) (WS) (Rated/Unrated)	Summertime: Number 9A 1948	Tree Number Two	Gangster Number 1