The number 18423
18423 is a composite number with 12 divisors. Its prime factorisation is × 23 × 89. Divisors (12): 1, 3, 9, 23, 69, 89, 207, 267, 801, 2047, 6141, 18423.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 18423: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
18423 is composite. Its prime factorisation is
- 3
The divisors add up to 28080; without 18423 itself that is 9657, so 18423 is deficient (9657 is less than 18423). Euler's totient φ(18423) = 11616 numbers up to 18423 share no factor with it.
- 4
The digits of 18423 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 123 steps to reach 1.
LaTeX source of the formulas on this page
\[ 18423 = 3^{2} \times 23 \times 89 \]18423 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 28080 |
| Euler totient φ(n) | 11616 |
| Square | 339406929 |
| Cube | 6252893852967 |
| Square root | 135.731352 (= 3√2047) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 123 |
| Scientific notation | 1.8423 × |
18423 in other forms
| Form | Value |
|---|---|
| In words | eighteen thousand four hundred and twenty-three |
| Binary (base 2) | 100011111110111 |
| Octal (base 8) | 43767 |
| Hexadecimal (base 16) | 47F7 |
| Base 3 | 221021100 |
| As time | 18423 seconds = 5 h 7 min 3 s |
Is 18423 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (18423 ÷ 3 = 6141) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | 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 | No (remainder 3) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 6) | 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 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (18423 ÷ 9 = 2047) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 3) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 18423 a prime number?
No. 18423 = × 23 × 89, so it is divisible by 3.
What are the factors of 18423?
1, 3, 9, 23, 69, 89, 207, 267, 801, 2047, 6141, 18423.
What is 18423 in binary?
100011111110111 (hexadecimal 47F7, octal 43767).
What is the square root of 18423?
About 135.7314, exactly 3√2047.
Is 18423 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 18423?
18423 is a happy number: repeatedly adding the squares of its digits reaches 1.