Discover a lot of information on the number 9: properties, mathematical operations, how to write it, symbolism, numerology, representations and many other interesting things!

## Numerology and symbolism of the number 9

The number 9 (nine) represents humanity, altruism. It symbolizes generosity, idealism and humanitarian vocations.

## Mathematical properties of 9

Is 9 a prime number? No
Is 9 a perfect number? No
Number of divisors 3
List of dividers 1, 3, 9
Sum of divisors 13

## How to write / spell 9 in letters?

In letters, the number 9 is written as: Nine. And in other languages? how does it spell?

9 in other languages
Write 9 in english Nine
Write 9 in french Neuf
Write 9 in spanish Nueve
Write 9 in portuguese Nove

Other ways to write 9
In letter Nine
In roman numeral IX
In binary 1001
In octal 11
In US dollars USD 9.00 (\$)
In euros 9,00 EUR (€)
Some related numbers
Previous number 8
Next number 10
Next prime number 11

## Mathematical operations

Operations and solutions
9*2 = 18 The double of 9 is 18
9*3 = 27 The triple of 9 is 27
9/2 = 4.5 The half of 9 is 4.500000
9/3 = 3 The third of 9 is 3.000000
92 = 81 The square of 9 is 81.000000
93 = 729 The cube of 9 is 729.000000
√9 = 3 The square root of 9 is 3.000000
log(9) = 2.1972245773362 The natural (Neperian) logarithm of 9 is 2.197225
log10(9) = 0.95424250943932 The decimal logarithm (base 10) of 9 is 0.954243
sin(9) = 0.41211848524176 The sine of 9 is 0.412118
cos(9) = -0.91113026188468 The cosine of 9 is -0.911130
tan(9) = -0.45231565944181 The tangent of 9 is -0.452316