The number 43987
43987 is the 4577th prime number. Its only divisors are 1 and 43987.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 43987: the 4577th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
43987 is prime, so its only factors are 1 and 43987. It is the 4577th prime; the next prime is 43991 and the one before is 43973.
- 3
The divisors add up to 43988; without 43987 itself that is 1, so 43987 is deficient (1 is less than 43987). Euler's totient φ(43987) = 43986 numbers up to 43987 share no factor with it.
- 4
The digits of 43987 add up to 31, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 150 steps to reach 1.
43987 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 43988 |
| Euler totient φ(n) | 43986 |
| Square | 1934856169 |
| Cube | 85108518305803 |
| Square root | 209.730780 |
| Digit sum / digital root | 31 / 4 |
| Collatz steps to 1 | 150 |
| Scientific notation | 4.3987 × |
43987 in other forms
| Form | Value |
|---|---|
| In words | forty-three thousand nine hundred and eighty-seven |
| Binary (base 2) | 1010101111010011 |
| Octal (base 8) | 125723 |
| Hexadecimal (base 16) | ABD3 |
| Base 3 | 2020100011 |
| As time | 43987 seconds = 12 h 13 min 7 s |
Is 43987 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 3) | 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 7) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | 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 43987 a prime number?
Yes. 43987 is divisible only by 1 and itself.
What are the factors of 43987?
1, 43987.
What is 43987 in binary?
1010101111010011 (hexadecimal ABD3, octal 125723).
What is the square root of 43987?
About 209.7308.
Is 43987 divisible by 3?
No. Its digits add up to 31, which is not a multiple of 3.
What is special about the number 43987?
43987 is the 4577th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.