The number 21046
21046 is a composite number with 8 divisors. Its prime factorisation is 2 × 17 × 619. Divisors (8): 1, 2, 17, 34, 619, 1238, 10523, 21046.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
21046 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
21046 is composite. Its prime factorisation is
- 3
The divisors add up to 33480; without 21046 itself that is 12434, so 21046 is deficient (12434 is less than 21046). Euler's totient φ(21046) = 9888 numbers up to 21046 share no factor with it.
- 4
The digits of 21046 add up to 13, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 180 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21046 = 2 \times 17 \times 619 \]
21046 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 33480 |
| Euler totient φ(n) | 9888 |
| Square | 442934116 |
| Cube | 9321991405336 |
| Square root | 145.072396 |
| Digit sum / digital root | 13 / 4 |
| Collatz steps to 1 | 180 |
| Scientific notation | 2.1046 × |
21046 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand and forty-six |
| Binary (base 2) | 101001000110110 |
| Octal (base 8) | 51066 |
| Hexadecimal (base 16) | 5236 |
| Base 3 | 1001212111 |
| As time | 21046 seconds = 5 h 50 min 46 s |
Is 21046 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (21046 ÷ 2 = 10523) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | 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 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 4) | 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 4) | 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 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 10) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 21046 a prime number?
No. 21046 = 2 × 17 × 619, so it is divisible by 2.
What are the factors of 21046?
1, 2, 17, 34, 619, 1238, 10523, 21046.
What is 21046 in binary?
101001000110110 (hexadecimal 5236, octal 51066).
What is the square root of 21046?
About 145.0724.
Is 21046 divisible by 3?
No. Its digits add up to 13, which is not a multiple of 3.
What is special about the number 21046?
It is a composite number with 8 divisors.