The number 21133
21133 is a composite number with 4 divisors. Its prime factorisation is 7 × 3019. Divisors (4): 1, 7, 3019, 21133.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 21133: a semiprime: 7 × 3019, the product of two primes.
- 2
21133 is composite. Its prime factorisation is
- 3
The divisors add up to 24160; without 21133 itself that is 3027, so 21133 is deficient (3027 is less than 21133). Euler's totient φ(21133) = 18108 numbers up to 21133 share no factor with it.
- 4
The digits of 21133 add up to 10, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 105 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21133 = 7 \times 3019 \]
21133 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 24160 |
| Euler totient φ(n) | 18108 |
| Square | 446603689 |
| Cube | 9438075759637 |
| Square root | 145.371937 |
| Digit sum / digital root | 10 / 1 |
| Collatz steps to 1 | 105 |
| Scientific notation | 2.1133 × |
21133 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand one hundred and thirty-three |
| Binary (base 2) | 101001010001101 |
| Octal (base 8) | 51215 |
| Hexadecimal (base 16) | 528D |
| Base 3 | 1001222201 |
| As time | 21133 seconds = 5 h 52 min 13 s |
Is 21133 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | 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 1) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 1) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (21133 ÷ 7 = 3019) | 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 3) | 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 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 21133 a prime number?
No. 21133 = 7 × 3019, so it is divisible by 7.
What are the factors of 21133?
1, 7, 3019, 21133.
What is 21133 in binary?
101001010001101 (hexadecimal 528D, octal 51215).
What is the square root of 21133?
About 145.3719.
Is 21133 divisible by 3?
No. Its digits add up to 10, which is not a multiple of 3.
What is special about the number 21133?
21133 is a semiprime: 7 × 3019, the product of two primes.