The number 12387
12387 is a composite number with 4 divisors. Its prime factorisation is 3 × 4129. Divisors (4): 1, 3, 4129, 12387.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 12387: a semiprime: 3 × 4129, the product of two primes.
- 2
12387 is composite. Its prime factorisation is
- 3
The divisors add up to 16520; without 12387 itself that is 4133, so 12387 is deficient (4133 is less than 12387). Euler's totient φ(12387) = 8256 numbers up to 12387 share no factor with it.
- 4
The digits of 12387 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 187 steps to reach 1.
LaTeX source of the formulas on this page
\[ 12387 = 3 \times 4129 \]
12387 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 16520 |
| Euler totient φ(n) | 8256 |
| Square | 153437769 |
| Cube | 1900633644603 |
| Square root | 111.296900 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 187 |
| Scientific notation | 1.2387 × |
12387 in other forms
| Form | Value |
|---|---|
| In words | twelve thousand three hundred and eighty-seven |
| Binary (base 2) | 11000001100011 |
| Octal (base 8) | 30143 |
| Hexadecimal (base 16) | 3063 |
| Base 3 | 121222210 |
| As time | 12387 seconds = 3 h 26 min 27 s |
Is 12387 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 (12387 ÷ 3 = 4129) | 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 4) | 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 1) | 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 12387 a prime number?
No. 12387 = 3 × 4129, so it is divisible by 3.
What are the factors of 12387?
1, 3, 4129, 12387.
What is 12387 in binary?
11000001100011 (hexadecimal 3063, octal 30143).
What is the square root of 12387?
About 111.2969.
Is 12387 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 12387?
12387 is a semiprime: 3 × 4129, the product of two primes.