9
Number 9 properties
- Perfect square
- Palindrome
- Harshad
- Armstrong
- 9 is an odd number.
- 9 is a palindrome.
- 9 is a perfect square (3 × 3).
- 9 is an Armstrong (or Narcissistic) number, which means it is the sum of its own digits each raised to the power of the number of digits.
- 9 is a Harshad number, which means it is divisible by the sum of its digits (9 = 9, and 9 is divisible by 9).
Prime factorization
Prime factorization of 9: 3^2.
Divisors
Divisor count: 3
1, 3, 9
Factors of 9 are: 1, 3, 9.
Representations
In octal, 9 is represented as 11.
In binary, 9 is represented as 1001.
In hex, 9 is represented as 9.
Roman numeral: IX
Curiosities
- 9 is a perfect square, so it forms a square grid with equal side lengths.
- 9 reads the same from left to right and right to left.
- 9 is divisible by the sum of its digits.
Related numbers
Nearby primes: 3, 5, 7, 11, 13, 17
Quick answers
Is 9 prime?
No, 9 is not prime.
What are the factors of 9?
1, 3, 9
What is 9 in binary?
1001