The number 7887
7887 is a palindrome: it reads 7887 backwards too. Its prime factorisation is 3 × 11 × 239. Divisors (8): 1, 3, 11, 33, 239, 717, 2629, 7887.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 7887: a palindrome: it reads 7887 backwards too; a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
7887 is composite. Its prime factorisation is
- 3
The divisors add up to 11520; without 7887 itself that is 3633, so 7887 is deficient (3633 is less than 7887). Euler's totient φ(7887) = 4760 numbers up to 7887 share no factor with it.
- 4
The digits of 7887 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 176 steps to reach 1.
LaTeX source of the formulas on this page
\[ 7887 = 3 \times 11 \times 239 \]
7887 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 11520 |
| Euler totient φ(n) | 4760 |
| Square | 62204769 |
| Cube | 490609013103 |
| Square root | 88.808783 |
| Digit sum / digital root | 30 / 3 |
| Collatz steps to 1 | 176 |
| Scientific notation | 7.887 × |
7887 in other forms
| Form | Value |
|---|---|
| In words | seven thousand eight hundred and eighty-seven |
| Binary (base 2) | 1111011001111 |
| Octal (base 8) | 17317 |
| Hexadecimal (base 16) | 1ECF |
| Base 3 | 101211010 |
| As time | 7887 seconds = 2 h 11 min 27 s |
Is 7887 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 (7887 ÷ 3 = 2629) | 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 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 7) | 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 | Yes (7887 ÷ 11 = 717) | 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 7887 a prime number?
No. 7887 = 3 × 11 × 239, so it is divisible by 3.
What are the factors of 7887?
1, 3, 11, 33, 239, 717, 2629, 7887.
What is 7887 in binary?
1111011001111 (hexadecimal 1ECF, octal 17317).
What is the square root of 7887?
About 88.8088.
Is 7887 divisible by 3?
Yes. Its digits add up to 30, a multiple of 3.
What is special about the number 7887?
7887 is a palindrome: it reads 7887 backwards too; a happy number: repeatedly adding the squares of its digits reaches 1.