The number 7689
7689 is a composite number with 8 divisors. Its prime factorisation is 3 × 11 × 233. Divisors (8): 1, 3, 11, 33, 233, 699, 2563, 7689.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 7689: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
7689 is composite. Its prime factorisation is
- 3
The divisors add up to 11232; without 7689 itself that is 3543, so 7689 is deficient (3543 is less than 7689). Euler's totient φ(7689) = 4640 numbers up to 7689 share no factor with it.
- 4
The digits of 7689 add up to 30, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 57 steps to reach 1.
LaTeX source of the formulas on this page
\[ 7689 = 3 \times 11 \times 233 \]
7689 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 11232 |
| Euler totient φ(n) | 4640 |
| Square | 59120721 |
| Cube | 454579223769 |
| Square root | 87.686943 |
| Digit sum / digital root | 30 / 3 |
| Collatz steps to 1 | 57 |
| Scientific notation | 7.689 × |
7689 in other forms
| Form | Value |
|---|---|
| In words | seven thousand six hundred and eighty-nine |
| Binary (base 2) | 1111000001001 |
| Octal (base 8) | 17011 |
| Hexadecimal (base 16) | 1E09 |
| Base 3 | 101112210 |
| As time | 7689 seconds = 2 h 8 min 9 s |
Is 7689 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 (7689 ÷ 3 = 2563) | 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 4) | 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 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 1) | 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 9) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (7689 ÷ 11 = 699) | 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 7689 a prime number?
No. 7689 = 3 × 11 × 233, so it is divisible by 3.
What are the factors of 7689?
1, 3, 11, 33, 233, 699, 2563, 7689.
What is 7689 in binary?
1111000001001 (hexadecimal 1E09, octal 17011).
What is the square root of 7689?
About 87.6869.
Is 7689 divisible by 3?
Yes. Its digits add up to 30, a multiple of 3.
What is special about the number 7689?
7689 is a happy number: repeatedly adding the squares of its digits reaches 1.