The number 87309
87309 is a composite number with 12 divisors. Its prime factorisation is × 89 × 109. Divisors (12): 1, 3, 9, 89, 109, 267, 327, 801, 981, 9701, 29103, 87309.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 87309: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
87309 is composite. Its prime factorisation is
- 3
The divisors add up to 128700; without 87309 itself that is 41391, so 87309 is deficient (41391 is less than 87309). Euler's totient φ(87309) = 57024 numbers up to 87309 share no factor with it.
- 4
The digits of 87309 add up to 27, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 133 steps to reach 1.
LaTeX source of the formulas on this page
\[ 87309 = 3^{2} \times 89 \times 109 \]87309 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 128700 |
| Euler totient φ(n) | 57024 |
| Square | 7622861481 |
| Cube | 665544413044629 |
| Square root | 295.480964 (= 3√9701) |
| Digit sum / digital root | 27 / 9 |
| Collatz steps to 1 | 133 |
| Scientific notation | 8.7309 × |
87309 in other forms
| Form | Value |
|---|---|
| In words | eighty-seven thousand three hundred and nine |
| Binary (base 2) | 10101010100001101 |
| Octal (base 8) | 252415 |
| Hexadecimal (base 16) | 1550D |
| Base 3 | 11102202200 |
| As time | 87309 seconds = 24 h 15 min 9 s |
Is 87309 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 (87309 ÷ 3 = 29103) | 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 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 | Yes (87309 ÷ 9 = 9701) | 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 2) | 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 87309 a prime number?
No. 87309 = × 89 × 109, so it is divisible by 3.
What are the factors of 87309?
1, 3, 9, 89, 109, 267, 327, 801, 981, 9701, 29103, 87309.
What is 87309 in binary?
10101010100001101 (hexadecimal 1550D, octal 252415).
What is the square root of 87309?
About 295.4810, exactly 3√9701.
Is 87309 divisible by 3?
Yes. Its digits add up to 27, a multiple of 3.
What is special about the number 87309?
87309 is a happy number: repeatedly adding the squares of its digits reaches 1.