The number 9021
9021 is a composite number with 8 divisors. Its prime factorisation is 3 × 31 × 97. Divisors (8): 1, 3, 31, 93, 97, 291, 3007, 9021.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 9021: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
9021 is composite. Its prime factorisation is
- 3
The divisors add up to 12544; without 9021 itself that is 3523, so 9021 is deficient (3523 is less than 9021). Euler's totient φ(9021) = 5760 numbers up to 9021 share no factor with it.
- 4
The digits of 9021 add up to 12, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 140 steps to reach 1.
LaTeX source of the formulas on this page
\[ 9021 = 3 \times 31 \times 97 \]
9021 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 12544 |
| Euler totient φ(n) | 5760 |
| Square | 81378441 |
| Cube | 734114916261 |
| Square root | 94.978945 |
| Digit sum / digital root | 12 / 3 |
| Collatz steps to 1 | 140 |
| Scientific notation | 9.021 × |
9021 in other forms
| Form | Value |
|---|---|
| In words | nine thousand and twenty-one |
| Binary (base 2) | 10001100111101 |
| Octal (base 8) | 21475 |
| Hexadecimal (base 16) | 233D |
| Base 3 | 110101010 |
| As time | 9021 seconds = 2 h 30 min 21 s |
Is 9021 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 | Yes (9021 ÷ 3 = 3007) | 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 1) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 3) | 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 1) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 9021 a prime number?
No. 9021 = 3 × 31 × 97, so it is divisible by 3.
What are the factors of 9021?
1, 3, 31, 93, 97, 291, 3007, 9021.
What is 9021 in binary?
10001100111101 (hexadecimal 233D, octal 21475).
What is the square root of 9021?
About 94.9789.
Is 9021 divisible by 3?
Yes. Its digits add up to 12, a multiple of 3.
What is special about the number 9021?
9021 is a happy number: repeatedly adding the squares of its digits reaches 1.