The number 81441
81441 is a composite number with 6 divisors. Its prime factorisation is × 9049. Divisors (6): 1, 3, 9, 9049, 27147, 81441.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
81441 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
81441 is composite. Its prime factorisation is
- 3
The divisors add up to 117650; without 81441 itself that is 36209, so 81441 is deficient (36209 is less than 81441). Euler's totient φ(81441) = 54288 numbers up to 81441 share no factor with it.
- 4
The digits of 81441 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 200 steps to reach 1.
LaTeX source of the formulas on this page
\[ 81441 = 3^{2} \times 9049 \]81441 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 117650 |
| Euler totient φ(n) | 54288 |
| Square | 6632636481 |
| Cube | 540168547649121 |
| Square root | 285.378696 (= 3√9049) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 200 |
| Scientific notation | 8.1441 × |
81441 in other forms
| Form | Value |
|---|---|
| In words | eighty-one thousand four hundred and forty-one |
| Binary (base 2) | 10011111000100001 |
| Octal (base 8) | 237041 |
| Hexadecimal (base 16) | 13E21 |
| Base 3 | 11010201100 |
| As time | 81441 seconds = 22 h 37 min 21 s |
Is 81441 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 | Yes (81441 ÷ 3 = 27147) | 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 3) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | 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 | Yes (81441 ÷ 9 = 9049) | 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 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 81441 a prime number?
No. 81441 = × 9049, so it is divisible by 3.
What are the factors of 81441?
1, 3, 9, 9049, 27147, 81441.
What is 81441 in binary?
10011111000100001 (hexadecimal 13E21, octal 237041).
What is the square root of 81441?
About 285.3787, exactly 3√9049.
Is 81441 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 81441?
It is a composite number with 6 divisors.