The number 21446
21446 is a composite number with 4 divisors. Its prime factorisation is 2 × 10723. Divisors (4): 1, 2, 10723, 21446.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 21446: a semiprime: 2 × 10723, the product of two primes.
- 2
21446 is composite. Its prime factorisation is
- 3
The divisors add up to 32172; without 21446 itself that is 10726, so 21446 is deficient (10726 is less than 21446). Euler's totient φ(21446) = 10722 numbers up to 21446 share no factor with it.
- 4
The digits of 21446 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 74 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21446 = 2 \times 10723 \]
21446 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 32172 |
| Euler totient φ(n) | 10722 |
| Square | 459930916 |
| Cube | 9863678424536 |
| Square root | 146.444529 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 74 |
| Scientific notation | 2.1446 × |
21446 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand four hundred and forty-six |
| Binary (base 2) | 101001111000110 |
| Octal (base 8) | 51706 |
| Hexadecimal (base 16) | 53C6 |
| Base 3 | 1002102022 |
| As time | 21446 seconds = 5 h 57 min 26 s |
Is 21446 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (21446 ÷ 2 = 10723) | 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 1) | 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 5) | 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 8) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 6) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 7) | 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 21446 a prime number?
No. 21446 = 2 × 10723, so it is divisible by 2.
What are the factors of 21446?
1, 2, 10723, 21446.
What is 21446 in binary?
101001111000110 (hexadecimal 53C6, octal 51706).
What is the square root of 21446?
About 146.4445.
Is 21446 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 21446?
21446 is a semiprime: 2 × 10723, the product of two primes.