The number 3989
3989 is the 550th prime number. Its only divisors are 1 and 3989.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 3989: the 550th prime number.
- 2
3989 is prime, so its only factors are 1 and 3989. It is the 550th prime; the next prime is 4001 and the one before is 3967.
- 3
The divisors add up to 3990; without 3989 itself that is 1, so 3989 is deficient (1 is less than 3989). Euler's totient φ(3989) = 3988 numbers up to 3989 share no factor with it.
- 4
The digits of 3989 add up to 29, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 51 steps to reach 1.
3989 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 3990 |
| Euler totient φ(n) | 3988 |
| Square | 15912121 |
| Cube | 63473450669 |
| Square root | 63.158531 |
| Digit sum / digital root | 29 / 2 |
| Collatz steps to 1 | 51 |
| Scientific notation | 3.989 × |
3989 in other forms
| Form | Value |
|---|---|
| In words | three thousand nine hundred and eighty-nine |
| Roman numerals | MMMCMLXXXIX |
| Binary (base 2) | 111110010101 |
| Octal (base 8) | 7625 |
| Hexadecimal (base 16) | F95 |
| Base 3 | 12110202 |
| As time | 3989 seconds = 1 h 6 min 29 s |
Is 3989 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 1) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 4) | 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 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 9) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 3989 a prime number?
Yes. 3989 is divisible only by 1 and itself.
What are the factors of 3989?
1, 3989.
What is 3989 in binary?
111110010101 (hexadecimal F95, octal 7625).
What is the square root of 3989?
About 63.1585.
What is 3989 in Roman numerals?
MMMCMLXXXIX.
Is 3989 divisible by 3?
No. Its digits add up to 29, which is not a multiple of 3.
What is special about the number 3989?
3989 is the 550th prime number.