The number 38987
38987 is a composite number with 4 divisors. Its prime factorisation is 13 × 2999. Divisors (4): 1, 13, 2999, 38987.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 38987: a semiprime: 13 × 2999, the product of two primes.
- 2
38987 is composite. Its prime factorisation is
- 3
The divisors add up to 42000; without 38987 itself that is 3013, so 38987 is deficient (3013 is less than 38987). Euler's totient φ(38987) = 35976 numbers up to 38987 share no factor with it.
- 4
The digits of 38987 add up to 35, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 137 steps to reach 1.
LaTeX source of the formulas on this page
\[ 38987 = 13 \times 2999 \]
38987 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 42000 |
| Euler totient φ(n) | 35976 |
| Square | 1519986169 |
| Cube | 59259700770803 |
| Square root | 197.451260 |
| Digit sum / digital root | 35 / 8 |
| Collatz steps to 1 | 137 |
| Scientific notation | 3.8987 × |
38987 in other forms
| Form | Value |
|---|---|
| In words | thirty-eight thousand nine hundred and eighty-seven |
| Binary (base 2) | 1001100001001011 |
| Octal (base 8) | 114113 |
| Hexadecimal (base 16) | 984B |
| Base 3 | 1222110222 |
| As time | 38987 seconds = 10 h 49 min 47 s |
Is 38987 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 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 5) | 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 8) | 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 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 38987 a prime number?
No. 38987 = 13 × 2999, so it is divisible by 13.
What are the factors of 38987?
1, 13, 2999, 38987.
What is 38987 in binary?
1001100001001011 (hexadecimal 984B, octal 114113).
What is the square root of 38987?
About 197.4513.
Is 38987 divisible by 3?
No. Its digits add up to 35, which is not a multiple of 3.
What is special about the number 38987?
38987 is a semiprime: 13 × 2999, the product of two primes.