The number 2389
2389 is the 355th prime number. Its only divisors are 1 and 2389.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 2389: the 355th prime number.
- 2
2389 is prime, so its only factors are 1 and 2389. It is the 355th prime; the next prime is 2393 and the one before is 2383.
- 3
The divisors add up to 2390; without 2389 itself that is 1, so 2389 is deficient (1 is less than 2389). Euler's totient φ(2389) = 2388 numbers up to 2389 share no factor with it.
- 4
The digits of 2389 add up to 22, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 27 steps to reach 1.
2389 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 2390 |
| Euler totient φ(n) | 2388 |
| Square | 5707321 |
| Cube | 13634789869 |
| Square root | 48.877398 |
| Digit sum / digital root | 22 / 4 |
| Collatz steps to 1 | 27 |
| Scientific notation | 2.389 × |
2389 in other forms
| Form | Value |
|---|---|
| In words | two thousand three hundred and eighty-nine |
| Roman numerals | MMCCCLXXXIX |
| Binary (base 2) | 100101010101 |
| Octal (base 8) | 4525 |
| Hexadecimal (base 16) | 955 |
| Base 3 | 10021111 |
| As time | 2389 seconds = 39 min 49 s |
Is 2389 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 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 1) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 2) | 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 4) | 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 2) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 2389 a prime number?
Yes. 2389 is divisible only by 1 and itself.
What are the factors of 2389?
1, 2389.
What is 2389 in binary?
100101010101 (hexadecimal 955, octal 4525).
What is the square root of 2389?
About 48.8774.
What is 2389 in Roman numerals?
MMCCCLXXXIX.
Is 2389 divisible by 3?
No. Its digits add up to 22, which is not a multiple of 3.
What is special about the number 2389?
2389 is the 355th prime number.