The number 97721
97721 is a composite number with 4 divisors. Its prime factorisation is 13 × 7517. Divisors (4): 1, 13, 7517, 97721.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 97721: a semiprime: 13 × 7517, the product of two primes.
- 2
97721 is composite. Its prime factorisation is
- 3
The divisors add up to 105252; without 97721 itself that is 7531, so 97721 is deficient (7531 is less than 97721). Euler's totient φ(97721) = 90192 numbers up to 97721 share no factor with it.
- 4
The digits of 97721 add up to 26, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 159 steps to reach 1.
LaTeX source of the formulas on this page
\[ 97721 = 13 \times 7517 \]
97721 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 105252 |
| Euler totient φ(n) | 90192 |
| Square | 9549393841 |
| Cube | 933176315536361 |
| Square root | 312.603583 |
| Digit sum / digital root | 26 / 8 |
| Collatz steps to 1 | 159 |
| Scientific notation | 9.7721 × |
97721 in other forms
| Form | Value |
|---|---|
| In words | ninety-seven thousand seven hundred and twenty-one |
| Binary (base 2) | 10111110110111001 |
| Octal (base 8) | 276671 |
| Hexadecimal (base 16) | 17DB9 |
| Base 3 | 11222001022 |
| As time | 97721 seconds = 27 h 8 min 41 s |
Is 97721 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 2) | 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 5) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 1) | 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 8) | 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 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 97721 a prime number?
No. 97721 = 13 × 7517, so it is divisible by 13.
What are the factors of 97721?
1, 13, 7517, 97721.
What is 97721 in binary?
10111110110111001 (hexadecimal 17DB9, octal 276671).
What is the square root of 97721?
About 312.6036.
Is 97721 divisible by 3?
No. Its digits add up to 26, which is not a multiple of 3.
What is special about the number 97721?
97721 is a semiprime: 13 × 7517, the product of two primes.