The number 4987
4987 is the 667th prime number. Its only divisors are 1 and 4987.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 4987: the 667th prime number.
- 2
4987 is prime, so its only factors are 1 and 4987. It is the 667th prime; the next prime is 4993 and the one before is 4973.
- 3
The divisors add up to 4988; without 4987 itself that is 1, so 4987 is deficient (1 is less than 4987). Euler's totient φ(4987) = 4986 numbers up to 4987 share no factor with it.
- 4
The digits of 4987 add up to 28, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 165 steps to reach 1.
4987 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 4988 |
| Euler totient φ(n) | 4986 |
| Square | 24870169 |
| Cube | 124027532803 |
| Square root | 70.618694 |
| Digit sum / digital root | 28 / 1 |
| Collatz steps to 1 | 165 |
| Scientific notation | 4.987 × |
4987 in other forms
| Form | Value |
|---|---|
| In words | four thousand nine hundred and eighty-seven |
| Binary (base 2) | 1001101111011 |
| Octal (base 8) | 11573 |
| Hexadecimal (base 16) | 137B |
| Base 3 | 20211201 |
| As time | 4987 seconds = 1 h 23 min 7 s |
Is 4987 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 3) | 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 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 4) | 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 4987 a prime number?
Yes. 4987 is divisible only by 1 and itself.
What are the factors of 4987?
1, 4987.
What is 4987 in binary?
1001101111011 (hexadecimal 137B, octal 11573).
What is the square root of 4987?
About 70.6187.
Is 4987 divisible by 3?
No. Its digits add up to 28, which is not a multiple of 3.
What is special about the number 4987?
4987 is the 667th prime number.