The number 67561
67561 is a composite number with 4 divisors. Its prime factorisation is 13 × 5197. Divisors (4): 1, 13, 5197, 67561.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 67561: a semiprime: 13 × 5197, the product of two primes.
- 2
67561 is composite. Its prime factorisation is
- 3
The divisors add up to 72772; without 67561 itself that is 5211, so 67561 is deficient (5211 is less than 67561). Euler's totient φ(67561) = 62352 numbers up to 67561 share no factor with it.
- 4
The digits of 67561 add up to 25, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 197 steps to reach 1.
LaTeX source of the formulas on this page
\[ 67561 = 13 \times 5197 \]
67561 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 72772 |
| Euler totient φ(n) | 62352 |
| Square | 4564488721 |
| Cube | 308381422479481 |
| Square root | 259.924989 |
| Digit sum / digital root | 25 / 7 |
| Collatz steps to 1 | 197 |
| Scientific notation | 6.7561 × |
67561 in other forms
| Form | Value |
|---|---|
| In words | sixty-seven thousand five hundred and sixty-one |
| Binary (base 2) | 10000011111101001 |
| Octal (base 8) | 203751 |
| Hexadecimal (base 16) | 107E9 |
| Base 3 | 10102200021 |
| As time | 67561 seconds = 18 h 46 min 1 s |
Is 67561 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 1) | 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 1) | 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 7) | 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 10) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 67561 a prime number?
No. 67561 = 13 × 5197, so it is divisible by 13.
What are the factors of 67561?
1, 13, 5197, 67561.
What is 67561 in binary?
10000011111101001 (hexadecimal 107E9, octal 203751).
What is the square root of 67561?
About 259.9250.
Is 67561 divisible by 3?
No. Its digits add up to 25, which is not a multiple of 3.
What is special about the number 67561?
67561 is a semiprime: 13 × 5197, the product of two primes.