The number 24381
24381 is a composite number with 20 divisors. Its prime factorisation is × 7 × 43. Divisors (20): 1, 3, 7, 9, 21, 27, 43, 63, 81, 129, 189, 301, 387, 567, 903, 1161 … 24381.
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How to work it out
- 1
What is special about 24381: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
24381 is composite. Its prime factorisation is
- 3
The divisors add up to 42592; without 24381 itself that is 18211, so 24381 is deficient (18211 is less than 24381). Euler's totient φ(24381) = 13608 numbers up to 24381 share no factor with it.
- 4
The digits of 24381 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 64 steps to reach 1.
LaTeX source of the formulas on this page
\[ 24381 = 3^{4} \times 7 \times 43 \]24381 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 20 |
| Sum of divisors | 42592 |
| Euler totient φ(n) | 13608 |
| Square | 594433161 |
| Cube | 14492874898341 |
| Square root | 156.144164 (= 9√301) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 64 |
| Scientific notation | 2.4381 × |
24381 in other forms
| Form | Value |
|---|---|
| In words | twenty-four thousand three hundred and eighty-one |
| Binary (base 2) | 101111100111101 |
| Octal (base 8) | 57475 |
| Hexadecimal (base 16) | 5F3D |
| Base 3 | 1020110000 |
| As time | 24381 seconds = 6 h 46 min 21 s |
Is 24381 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 (24381 ÷ 3 = 8127) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 1) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 1) | 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 | Yes (24381 ÷ 7 = 3483) | 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (24381 ÷ 9 = 2709) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 24381 a prime number?
No. 24381 = × 7 × 43, so it is divisible by 3.
What are the factors of 24381?
1, 3, 7, 9, 21, 27, 43, 63, 81, 129, 189, 301, 387, 567, 903, 1161, 2709, 3483, 8127, 24381.
What is 24381 in binary?
101111100111101 (hexadecimal 5F3D, octal 57475).
What is the square root of 24381?
About 156.1442, exactly 9√301.
Is 24381 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 24381?
24381 is a happy number: repeatedly adding the squares of its digits reaches 1.