The number 18642
18642 is a composite number with 16 divisors. Its prime factorisation is 2 × 3 × 13 × 239. Divisors (16): 1, 2, 3, 6, 13, 26, 39, 78, 239, 478, 717, 1434, 3107, 6214, 9321, 18642.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
18642 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
18642 is composite. Its prime factorisation is
- 3
The divisors add up to 40320; without 18642 itself that is 21678, so 18642 is abundant (21678 is more than 18642). Euler's totient φ(18642) = 5712 numbers up to 18642 share no factor with it.
- 4
The digits of 18642 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 61 steps to reach 1.
LaTeX source of the formulas on this page
\[ 18642 = 2 \times 3 \times 13 \times 239 \]
18642 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 40320 |
| Euler totient φ(n) | 5712 |
| Square | 347524164 |
| Cube | 6478545465288 |
| Square root | 136.535710 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 61 |
| Scientific notation | 1.8642 × |
18642 in other forms
| Form | Value |
|---|---|
| In words | eighteen thousand six hundred and forty-two |
| Binary (base 2) | 100100011010010 |
| Octal (base 8) | 44322 |
| Hexadecimal (base 16) | 48D2 |
| Base 3 | 221120110 |
| As time | 18642 seconds = 5 h 10 min 42 s |
Is 18642 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (18642 ÷ 2 = 9321) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (18642 ÷ 3 = 6214) | 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 2) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (18642 ÷ 6 = 3107) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 1) | 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 3) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 2) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 8) | 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 18642 a prime number?
No. 18642 = 2 × 3 × 13 × 239, so it is divisible by 2.
What are the factors of 18642?
1, 2, 3, 6, 13, 26, 39, 78, 239, 478, 717, 1434, 3107, 6214, 9321, 18642.
What is 18642 in binary?
100100011010010 (hexadecimal 48D2, octal 44322).
What is the square root of 18642?
About 136.5357.
Is 18642 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 18642?
It is a composite number with 16 divisors.