The number 21342
21342 is a composite number with 8 divisors. Its prime factorisation is 2 × 3 × 3557. Divisors (8): 1, 2, 3, 6, 3557, 7114, 10671, 21342.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
21342 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
21342 is composite. Its prime factorisation is
- 3
The divisors add up to 42696; without 21342 itself that is 21354, so 21342 is abundant (21354 is more than 21342). Euler's totient φ(21342) = 7112 numbers up to 21342 share no factor with it.
- 4
The digits of 21342 add up to 12, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 87 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21342 = 2 \times 3 \times 3557 \]
21342 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 42696 |
| Euler totient φ(n) | 7112 |
| Square | 455480964 |
| Cube | 9720874733688 |
| Square root | 146.089014 |
| Digit sum / digital root | 12 / 3 |
| Collatz steps to 1 | 87 |
| Scientific notation | 2.1342 × |
21342 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand three hundred and forty-two |
| Binary (base 2) | 101001101011110 |
| Octal (base 8) | 51536 |
| Hexadecimal (base 16) | 535E |
| Base 3 | 1002021110 |
| As time | 21342 seconds = 5 h 55 min 42 s |
Is 21342 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (21342 ÷ 2 = 10671) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (21342 ÷ 3 = 7114) | 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 (21342 ÷ 6 = 3557) | 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 6) | 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 2) | 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 21342 a prime number?
No. 21342 = 2 × 3 × 3557, so it is divisible by 2.
What are the factors of 21342?
1, 2, 3, 6, 3557, 7114, 10671, 21342.
What is 21342 in binary?
101001101011110 (hexadecimal 535E, octal 51536).
What is the square root of 21342?
About 146.0890.
Is 21342 divisible by 3?
Yes. Its digits add up to 12, a multiple of 3.
What is special about the number 21342?
It is a composite number with 8 divisors.