The number 72729
72729 is a composite number with 6 divisors. Its prime factorisation is × 8081. Divisors (6): 1, 3, 9, 8081, 24243, 72729.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
72729 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
72729 is composite. Its prime factorisation is
- 3
The divisors add up to 105066; without 72729 itself that is 32337, so 72729 is deficient (32337 is less than 72729). Euler's totient φ(72729) = 48480 numbers up to 72729 share no factor with it.
- 4
The digits of 72729 add up to 27, 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
\[ 72729 = 3^{2} \times 8081 \]72729 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 105066 |
| Euler totient φ(n) | 48480 |
| Square | 5289507441 |
| Cube | 384700586676489 |
| Square root | 269.683147 (= 3√8081) |
| Digit sum / digital root | 27 / 9 |
| Collatz steps to 1 | 42 |
| Scientific notation | 7.2729 × |
72729 in other forms
| Form | Value |
|---|---|
| In words | seventy-two thousand seven hundred and twenty-nine |
| Binary (base 2) | 10001110000011001 |
| Octal (base 8) | 216031 |
| Hexadecimal (base 16) | 11C19 |
| Base 3 | 10200202200 |
| As time | 72729 seconds = 20 h 12 min 9 s |
Is 72729 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 (72729 ÷ 3 = 24243) | 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 4) | 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 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 | Yes (72729 ÷ 9 = 8081) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 9) | 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 72729 a prime number?
No. 72729 = × 8081, so it is divisible by 3.
What are the factors of 72729?
1, 3, 9, 8081, 24243, 72729.
What is 72729 in binary?
10001110000011001 (hexadecimal 11C19, octal 216031).
What is the square root of 72729?
About 269.6831, exactly 3√8081.
Is 72729 divisible by 3?
Yes. Its digits add up to 27, a multiple of 3.
What is special about the number 72729?
It is a composite number with 6 divisors.