The number 40871
40871 is a composite number with 4 divisors. Its prime factorisation is 23 × 1777. Divisors (4): 1, 23, 1777, 40871.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 40871: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 23 × 1777, the product of two primes.
- 2
40871 is composite. Its prime factorisation is
- 3
The divisors add up to 42672; without 40871 itself that is 1801, so 40871 is deficient (1801 is less than 40871). Euler's totient φ(40871) = 39072 numbers up to 40871 share no factor with it.
- 4
The digits of 40871 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 212 steps to reach 1.
LaTeX source of the formulas on this page
\[ 40871 = 23 \times 1777 \]
40871 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 42672 |
| Euler totient φ(n) | 39072 |
| Square | 1670438641 |
| Cube | 68272497696311 |
| Square root | 202.165774 |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 212 |
| Scientific notation | 4.0871 × |
40871 in other forms
| Form | Value |
|---|---|
| In words | forty thousand eight hundred and seventy-one |
| Binary (base 2) | 1001111110100111 |
| Octal (base 8) | 117647 |
| Hexadecimal (base 16) | 9FA7 |
| Base 3 | 2002001202 |
| As time | 40871 seconds = 11 h 21 min 11 s |
Is 40871 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 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 1) | 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 5) | 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 7) | 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 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 6) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 40871 a prime number?
No. 40871 = 23 × 1777, so it is divisible by 23.
What are the factors of 40871?
1, 23, 1777, 40871.
What is 40871 in binary?
1001111110100111 (hexadecimal 9FA7, octal 117647).
What is the square root of 40871?
About 202.1658.
Is 40871 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 40871?
40871 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 23 × 1777, the product of two primes.