The number 8787
8787 is a composite number with 8 divisors. Its prime factorisation is 3 × 29 × 101. Divisors (8): 1, 3, 29, 87, 101, 303, 2929, 8787.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 8787: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
8787 is composite. Its prime factorisation is
- 3
The divisors add up to 12240; without 8787 itself that is 3453, so 8787 is deficient (3453 is less than 8787). Euler's totient φ(8787) = 5600 numbers up to 8787 share no factor with it.
- 4
The digits of 8787 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 140 steps to reach 1.
LaTeX source of the formulas on this page
\[ 8787 = 3 \times 29 \times 101 \]
8787 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 12240 |
| Euler totient φ(n) | 5600 |
| Square | 77211369 |
| Cube | 678456299403 |
| Square root | 93.738999 |
| Digit sum / digital root | 30 / 3 |
| Collatz steps to 1 | 140 |
| Scientific notation | 8.787 × |
8787 in other forms
| Form | Value |
|---|---|
| In words | eight thousand seven hundred and eighty-seven |
| Binary (base 2) | 10001001010011 |
| Octal (base 8) | 21123 |
| Hexadecimal (base 16) | 2253 |
| Base 3 | 110001110 |
| As time | 8787 seconds = 2 h 26 min 27 s |
Is 8787 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 (8787 ÷ 3 = 2929) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 2) | 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 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 3) | 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 7) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 8787 a prime number?
No. 8787 = 3 × 29 × 101, so it is divisible by 3.
What are the factors of 8787?
1, 3, 29, 87, 101, 303, 2929, 8787.
What is 8787 in binary?
10001001010011 (hexadecimal 2253, octal 21123).
What is the square root of 8787?
About 93.7390.
Is 8787 divisible by 3?
Yes. Its digits add up to 30, a multiple of 3.
What is special about the number 8787?
8787 is a happy number: repeatedly adding the squares of its digits reaches 1.