The number 21122
21122 is a composite number with 8 divisors. Its prime factorisation is 2 × 59 × 179. Divisors (8): 1, 2, 59, 118, 179, 358, 10561, 21122.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
21122 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
21122 is composite. Its prime factorisation is
- 3
The divisors add up to 32400; without 21122 itself that is 11278, so 21122 is deficient (11278 is less than 21122). Euler's totient φ(21122) = 10324 numbers up to 21122 share no factor with it.
- 4
The digits of 21122 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 56 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21122 = 2 \times 59 \times 179 \]
21122 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 32400 |
| Euler totient φ(n) | 10324 |
| Square | 446138884 |
| Cube | 9423345507848 |
| Square root | 145.334098 |
| Digit sum / digital root | 8 / 8 |
| Collatz steps to 1 | 56 |
| Scientific notation | 2.1122 × |
21122 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand one hundred and twenty-two |
| Binary (base 2) | 101001010000010 |
| Octal (base 8) | 51202 |
| Hexadecimal (base 16) | 5282 |
| Base 3 | 1001222022 |
| As time | 21122 seconds = 5 h 52 min 2 s |
Is 21122 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (21122 ÷ 2 = 10561) | 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 3) | 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 | No (remainder 2) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 2) | 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 21122 a prime number?
No. 21122 = 2 × 59 × 179, so it is divisible by 2.
What are the factors of 21122?
1, 2, 59, 118, 179, 358, 10561, 21122.
What is 21122 in binary?
101001010000010 (hexadecimal 5282, octal 51202).
What is the square root of 21122?
About 145.3341.
Is 21122 divisible by 3?
No. Its digits add up to 8, which is not a multiple of 3.
What is special about the number 21122?
It is a composite number with 8 divisors.