The number 40987
40987 is a composite number with 4 divisors. Its prime factorisation is 17 × 2411. Divisors (4): 1, 17, 2411, 40987.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 40987: a semiprime: 17 × 2411, the product of two primes.
- 2
40987 is composite. Its prime factorisation is
- 3
The divisors add up to 43416; without 40987 itself that is 2429, so 40987 is deficient (2429 is less than 40987). Euler's totient φ(40987) = 38560 numbers up to 40987 share no factor with it.
- 4
The digits of 40987 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 88 steps to reach 1.
LaTeX source of the formulas on this page
\[ 40987 = 17 \times 2411 \]
40987 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 43416 |
| Euler totient φ(n) | 38560 |
| Square | 1679934169 |
| Cube | 68855461784803 |
| Square root | 202.452464 |
| Digit sum / digital root | 28 / 1 |
| Collatz steps to 1 | 88 |
| Scientific notation | 4.0987 × |
40987 in other forms
| Form | Value |
|---|---|
| In words | forty thousand nine hundred and eighty-seven |
| Binary (base 2) | 1010000000011011 |
| Octal (base 8) | 120033 |
| Hexadecimal (base 16) | A01B |
| Base 3 | 2002020001 |
| As time | 40987 seconds = 11 h 23 min 7 s |
Is 40987 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 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 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 1) | 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 40987 a prime number?
No. 40987 = 17 × 2411, so it is divisible by 17.
What are the factors of 40987?
1, 17, 2411, 40987.
What is 40987 in binary?
1010000000011011 (hexadecimal A01B, octal 120033).
What is the square root of 40987?
About 202.4525.
Is 40987 divisible by 3?
No. Its digits add up to 28, which is not a multiple of 3.
What is special about the number 40987?
40987 is a semiprime: 17 × 2411, the product of two primes.