The number 21344
21344 is a composite number with 24 divisors. Its prime factorisation is × 23 × 29. Divisors (24): 1, 2, 4, 8, 16, 23, 29, 32, 46, 58, 92, 116, 184, 232, 368, 464 … 21344.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
21344 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
21344 is composite. Its prime factorisation is
- 3
The divisors add up to 45360; without 21344 itself that is 24016, so 21344 is abundant (24016 is more than 21344). Euler's totient φ(21344) = 9856 numbers up to 21344 share no factor with it.
- 4
The digits of 21344 add up to 14, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 149 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21344 = 2^{5} \times 23 \times 29 \]21344 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 45360 |
| Euler totient φ(n) | 9856 |
| Square | 455566336 |
| Cube | 9723607875584 |
| Square root | 146.095859 (= 4√1334) |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 149 |
| Scientific notation | 2.1344 × |
21344 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand three hundred and forty-four |
| Binary (base 2) | 101001101100000 |
| Octal (base 8) | 51540 |
| Hexadecimal (base 16) | 5360 |
| Base 3 | 1002021112 |
| As time | 21344 seconds = 5 h 55 min 44 s |
Is 21344 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (21344 ÷ 2 = 10672) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 2) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (21344 ÷ 4 = 5336) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 4) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 2) | 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 | Yes (21344 ÷ 8 = 2668) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 5) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 4) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 21344 a prime number?
No. 21344 = × 23 × 29, so it is divisible by 2.
What are the factors of 21344?
1, 2, 4, 8, 16, 23, 29, 32, 46, 58, 92, 116, 184, 232, 368, 464, 667, 736, 928, 1334, 2668, 5336, 10672, 21344.
What is 21344 in binary?
101001101100000 (hexadecimal 5360, octal 51540).
What is the square root of 21344?
About 146.0959, exactly 4√1334.
Is 21344 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 21344?
It is a composite number with 24 divisors.