The number 72081
72081 is a composite number with 6 divisors. Its prime factorisation is × 8009. Divisors (6): 1, 3, 9, 8009, 24027, 72081.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
72081 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
72081 is composite. Its prime factorisation is
- 3
The divisors add up to 104130; without 72081 itself that is 32049, so 72081 is deficient (32049 is less than 72081). Euler's totient φ(72081) = 48048 numbers up to 72081 share no factor with it.
- 4
The digits of 72081 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 42 steps to reach 1.
LaTeX source of the formulas on this page
\[ 72081 = 3^{2} \times 8009 \]72081 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 104130 |
| Euler totient φ(n) | 48048 |
| Square | 5195670561 |
| Cube | 374509129707441 |
| Square root | 268.479049 (= 3√8009) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 42 |
| Scientific notation | 7.2081 × |
72081 in other forms
| Form | Value |
|---|---|
| In words | seventy-two thousand and eighty-one |
| Binary (base 2) | 10001100110010001 |
| Octal (base 8) | 214621 |
| Hexadecimal (base 16) | 11991 |
| Base 3 | 10122212200 |
| As time | 72081 seconds = 20 h 1 min 21 s |
Is 72081 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 (72081 ÷ 3 = 24027) | 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 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 1) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (72081 ÷ 9 = 8009) | 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 9) | 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 72081 a prime number?
No. 72081 = × 8009, so it is divisible by 3.
What are the factors of 72081?
1, 3, 9, 8009, 24027, 72081.
What is 72081 in binary?
10001100110010001 (hexadecimal 11991, octal 214621).
What is the square root of 72081?
About 268.4790, exactly 3√8009.
Is 72081 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 72081?
It is a composite number with 6 divisors.