The number 3689
3689 is a composite number with 8 divisors. Its prime factorisation is 7 × 17 × 31. Divisors (8): 1, 7, 17, 31, 119, 217, 527, 3689.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 3689: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
3689 is composite. Its prime factorisation is
- 3
The divisors add up to 4608; without 3689 itself that is 919, so 3689 is deficient (919 is less than 3689). Euler's totient φ(3689) = 2880 numbers up to 3689 share no factor with it.
- 4
The digits of 3689 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 100 steps to reach 1.
LaTeX source of the formulas on this page
\[ 3689 = 7 \times 17 \times 31 \]
3689 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 4608 |
| Euler totient φ(n) | 2880 |
| Square | 13608721 |
| Cube | 50202571769 |
| Square root | 60.737139 |
| Digit sum / digital root | 26 / 8 |
| Collatz steps to 1 | 100 |
| Scientific notation | 3.689 × |
3689 in other forms
| Form | Value |
|---|---|
| In words | three thousand six hundred and eighty-nine |
| Roman numerals | MMMDCLXXXIX |
| Binary (base 2) | 111001101001 |
| Octal (base 8) | 7151 |
| Hexadecimal (base 16) | E69 |
| Base 3 | 12001122 |
| As time | 3689 seconds = 1 h 1 min 29 s |
Is 3689 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 2) | 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 5) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (3689 ÷ 7 = 527) | 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 8) | 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 | No (remainder 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 3689 a prime number?
No. 3689 = 7 × 17 × 31, so it is divisible by 7.
What are the factors of 3689?
1, 7, 17, 31, 119, 217, 527, 3689.
What is 3689 in binary?
111001101001 (hexadecimal E69, octal 7151).
What is the square root of 3689?
About 60.7371.
What is 3689 in Roman numerals?
MMMDCLXXXIX.
Is 3689 divisible by 3?
No. Its digits add up to 26, which is not a multiple of 3.
What is special about the number 3689?
3689 is a happy number: repeatedly adding the squares of its digits reaches 1.