The number 72321
72321 is a composite number with 4 divisors. Its prime factorisation is 3 × 24107. Divisors (4): 1, 3, 24107, 72321.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 72321: a semiprime: 3 × 24107, the product of two primes.
- 2
72321 is composite. Its prime factorisation is
- 3
The divisors add up to 96432; without 72321 itself that is 24111, so 72321 is deficient (24111 is less than 72321). Euler's totient φ(72321) = 48212 numbers up to 72321 share no factor with it.
- 4
The digits of 72321 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 125 steps to reach 1.
LaTeX source of the formulas on this page
\[ 72321 = 3 \times 24107 \]
72321 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 96432 |
| Euler totient φ(n) | 48212 |
| Square | 5230327041 |
| Cube | 378262481932161 |
| Square root | 268.925640 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 125 |
| Scientific notation | 7.2321 × |
72321 in other forms
| Form | Value |
|---|---|
| In words | seventy-two thousand three hundred and twenty-one |
| Binary (base 2) | 10001101010000001 |
| Octal (base 8) | 215201 |
| Hexadecimal (base 16) | 11A81 |
| Base 3 | 10200012120 |
| As time | 72321 seconds = 20 h 5 min 21 s |
Is 72321 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 (72321 ÷ 3 = 24107) | 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 4) | 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 6) | 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 7) | 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 72321 a prime number?
No. 72321 = 3 × 24107, so it is divisible by 3.
What are the factors of 72321?
1, 3, 24107, 72321.
What is 72321 in binary?
10001101010000001 (hexadecimal 11A81, octal 215201).
What is the square root of 72321?
About 268.9256.
Is 72321 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 72321?
72321 is a semiprime: 3 × 24107, the product of two primes.