The number 13218
13218 is a composite number with 8 divisors. Its prime factorisation is 2 × 3 × 2203. Divisors (8): 1, 2, 3, 6, 2203, 4406, 6609, 13218.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 13218: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
13218 is composite. Its prime factorisation is
- 3
The divisors add up to 26448; without 13218 itself that is 13230, so 13218 is abundant (13230 is more than 13218). Euler's totient φ(13218) = 4404 numbers up to 13218 share no factor with it.
- 4
The digits of 13218 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 138 steps to reach 1.
LaTeX source of the formulas on this page
\[ 13218 = 2 \times 3 \times 2203 \]
13218 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 26448 |
| Euler totient φ(n) | 4404 |
| Square | 174715524 |
| Cube | 2309389796232 |
| Square root | 114.969561 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 138 |
| Scientific notation | 1.3218 × |
13218 in other forms
| Form | Value |
|---|---|
| In words | thirteen thousand two hundred and eighteen |
| Binary (base 2) | 11001110100010 |
| Octal (base 8) | 31642 |
| Hexadecimal (base 16) | 33A2 |
| Base 3 | 200010120 |
| As time | 13218 seconds = 3 h 40 min 18 s |
Is 13218 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (13218 ÷ 2 = 6609) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (13218 ÷ 3 = 4406) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (13218 ÷ 6 = 2203) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 2) | A number is divisible by 7 if double the last digit and subtract it from the rest: the result is a multiple of 7. |
| 8 | No (remainder 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 8) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 6) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 13218 a prime number?
No. 13218 = 2 × 3 × 2203, so it is divisible by 2.
What are the factors of 13218?
1, 2, 3, 6, 2203, 4406, 6609, 13218.
What is 13218 in binary?
11001110100010 (hexadecimal 33A2, octal 31642).
What is the square root of 13218?
About 114.9696.
Is 13218 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 13218?
13218 is a happy number: repeatedly adding the squares of its digits reaches 1.