The number 40081
40081 is a composite number with 4 divisors. Its prime factorisation is 149 × 269. Divisors (4): 1, 149, 269, 40081.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 40081: a semiprime: 149 × 269, the product of two primes.
- 2
40081 is composite. Its prime factorisation is
- 3
The divisors add up to 40500; without 40081 itself that is 419, so 40081 is deficient (419 is less than 40081). Euler's totient φ(40081) = 39664 numbers up to 40081 share no factor with it.
- 4
The digits of 40081 add up to 13, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 212 steps to reach 1.
LaTeX source of the formulas on this page
\[ 40081 = 149 \times 269 \]
40081 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 40500 |
| Euler totient φ(n) | 39664 |
| Square | 1606486561 |
| Cube | 64389587851441 |
| Square root | 200.202398 |
| Digit sum / digital root | 13 / 4 |
| Collatz steps to 1 | 212 |
| Scientific notation | 4.0081 × |
40081 in other forms
| Form | Value |
|---|---|
| In words | forty thousand and eighty-one |
| Binary (base 2) | 1001110010010001 |
| Octal (base 8) | 116221 |
| Hexadecimal (base 16) | 9C91 |
| Base 3 | 2000222111 |
| As time | 40081 seconds = 11 h 8 min 1 s |
Is 40081 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 1) | 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 1) | 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 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 8) | 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 40081 a prime number?
No. 40081 = 149 × 269, so it is divisible by 149.
What are the factors of 40081?
1, 149, 269, 40081.
What is 40081 in binary?
1001110010010001 (hexadecimal 9C91, octal 116221).
What is the square root of 40081?
About 200.2024.
Is 40081 divisible by 3?
No. Its digits add up to 13, which is not a multiple of 3.
What is special about the number 40081?
40081 is a semiprime: 149 × 269, the product of two primes.