The number 21050
21050 is a composite number with 12 divisors. Its prime factorisation is 2 × × 421. Divisors (12): 1, 2, 5, 10, 25, 50, 421, 842, 2105, 4210, 10525, 21050.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
21050 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
21050 is composite. Its prime factorisation is
- 3
The divisors add up to 39246; without 21050 itself that is 18196, so 21050 is deficient (18196 is less than 21050). Euler's totient φ(21050) = 8400 numbers up to 21050 share no factor with it.
- 4
The digits of 21050 add up to 8, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 193 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21050 = 2 \times 5^{2} \times 421 \]21050 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 39246 |
| Euler totient φ(n) | 8400 |
| Square | 443102500 |
| Cube | 9327307625000 |
| Square root | 145.086181 (= 5√842) |
| Digit sum / digital root | 8 / 8 |
| Collatz steps to 1 | 193 |
| Scientific notation | 2.105 × |
21050 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand and fifty |
| Binary (base 2) | 101001000111010 |
| Octal (base 8) | 51072 |
| Hexadecimal (base 16) | 523A |
| Base 3 | 1001212122 |
| As time | 21050 seconds = 5 h 50 min 50 s |
Is 21050 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (21050 ÷ 2 = 10525) | 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 | Yes (21050 ÷ 5 = 4210) | 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 | No (remainder 2) | 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 | Yes (21050 ÷ 10 = 2105) | 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 21050 a prime number?
No. 21050 = 2 × × 421, so it is divisible by 2.
What are the factors of 21050?
1, 2, 5, 10, 25, 50, 421, 842, 2105, 4210, 10525, 21050.
What is 21050 in binary?
101001000111010 (hexadecimal 523A, octal 51072).
What is the square root of 21050?
About 145.0862, exactly 5√842.
Is 21050 divisible by 3?
No. Its digits add up to 8, which is not a multiple of 3.
What is special about the number 21050?
It is a composite number with 12 divisors.