The number 4087
4087 is a composite number with 4 divisors. Its prime factorisation is 61 × 67. Divisors (4): 1, 61, 67, 4087.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 4087: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 61 × 67, the product of two primes.
- 2
4087 is composite. Its prime factorisation is
- 3
The divisors add up to 4216; without 4087 itself that is 129, so 4087 is deficient (129 is less than 4087). Euler's totient φ(4087) = 3960 numbers up to 4087 share no factor with it.
- 4
The digits of 4087 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 157 steps to reach 1.
LaTeX source of the formulas on this page
\[ 4087 = 61 \times 67 \]
4087 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 4216 |
| Euler totient φ(n) | 3960 |
| Square | 16703569 |
| Cube | 68267486503 |
| Square root | 63.929649 |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 157 |
| Scientific notation | 4.087 × |
4087 in other forms
| Form | Value |
|---|---|
| In words | four thousand and eighty-seven |
| Binary (base 2) | 111111110111 |
| Octal (base 8) | 7767 |
| Hexadecimal (base 16) | FF7 |
| Base 3 | 12121101 |
| As time | 4087 seconds = 1 h 8 min 7 s |
Is 4087 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 1) | 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 1) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 6) | 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 1) | 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 6) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 4087 a prime number?
No. 4087 = 61 × 67, so it is divisible by 61.
What are the factors of 4087?
1, 61, 67, 4087.
What is 4087 in binary?
111111110111 (hexadecimal FF7, octal 7767).
What is the square root of 4087?
About 63.9296.
Is 4087 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 4087?
4087 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 61 × 67, the product of two primes.