The number 21422
21422 is a composite number with 4 divisors. Its prime factorisation is 2 × 10711. Divisors (4): 1, 2, 10711, 21422.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 21422: a semiprime: 2 × 10711, the product of two primes.
- 2
21422 is composite. Its prime factorisation is
- 3
The divisors add up to 32136; without 21422 itself that is 10714, so 21422 is deficient (10714 is less than 21422). Euler's totient φ(21422) = 10710 numbers up to 21422 share no factor with it.
- 4
The digits of 21422 add up to 11, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 100 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21422 = 2 \times 10711 \]
21422 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 32136 |
| Euler totient φ(n) | 10710 |
| Square | 458902084 |
| Cube | 9830600443448 |
| Square root | 146.362564 |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 100 |
| Scientific notation | 2.1422 × |
21422 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand four hundred and twenty-two |
| Binary (base 2) | 101001110101110 |
| Octal (base 8) | 51656 |
| Hexadecimal (base 16) | 53AE |
| Base 3 | 1002101102 |
| As time | 21422 seconds = 5 h 57 min 2 s |
Is 21422 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (21422 ÷ 2 = 10711) | 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 | 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 | No (remainder 2) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 2) | 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 2) | 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 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 21422 a prime number?
No. 21422 = 2 × 10711, so it is divisible by 2.
What are the factors of 21422?
1, 2, 10711, 21422.
What is 21422 in binary?
101001110101110 (hexadecimal 53AE, octal 51656).
What is the square root of 21422?
About 146.3626.
Is 21422 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 21422?
21422 is a semiprime: 2 × 10711, the product of two primes.