The number 8990
8990 is a composite number with 16 divisors. Its prime factorisation is 2 × 5 × 29 × 31. Divisors (16): 1, 2, 5, 10, 29, 31, 58, 62, 145, 155, 290, 310, 899, 1798, 4495, 8990.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 8990: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
8990 is composite. Its prime factorisation is
- 3
The divisors add up to 17280; without 8990 itself that is 8290, so 8990 is deficient (8290 is less than 8990). Euler's totient φ(8990) = 3360 numbers up to 8990 share no factor with it.
- 4
The digits of 8990 add up to 26, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 78 steps to reach 1.
LaTeX source of the formulas on this page
\[ 8990 = 2 \times 5 \times 29 \times 31 \]
8990 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 17280 |
| Euler totient φ(n) | 3360 |
| Square | 80820100 |
| Cube | 726572699000 |
| Square root | 94.815611 |
| Digit sum / digital root | 26 / 8 |
| Collatz steps to 1 | 78 |
| Scientific notation | 8.99 × |
8990 in other forms
| Form | Value |
|---|---|
| In words | eight thousand nine hundred and ninety |
| Binary (base 2) | 10001100011110 |
| Octal (base 8) | 21436 |
| Hexadecimal (base 16) | 231E |
| Base 3 | 110022222 |
| As time | 8990 seconds = 2 h 29 min 50 s |
Is 8990 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (8990 ÷ 2 = 4495) | 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 (8990 ÷ 5 = 1798) | 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 2) | 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 8) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (8990 ÷ 10 = 899) | 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 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 8990 a prime number?
No. 8990 = 2 × 5 × 29 × 31, so it is divisible by 2.
What are the factors of 8990?
1, 2, 5, 10, 29, 31, 58, 62, 145, 155, 290, 310, 899, 1798, 4495, 8990.
What is 8990 in binary?
10001100011110 (hexadecimal 231E, octal 21436).
What is the square root of 8990?
About 94.8156.
Is 8990 divisible by 3?
No. Its digits add up to 26, which is not a multiple of 3.
What is special about the number 8990?
8990 is a happy number: repeatedly adding the squares of its digits reaches 1.