The number 55643
55643 is a composite number with 4 divisors. Its prime factorisation is 7 × 7949. Divisors (4): 1, 7, 7949, 55643.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 55643: a semiprime: 7 × 7949, the product of two primes.
- 2
55643 is composite. Its prime factorisation is
- 3
The divisors add up to 63600; without 55643 itself that is 7957, so 55643 is deficient (7957 is less than 55643). Euler's totient φ(55643) = 47688 numbers up to 55643 share no factor with it.
- 4
The digits of 55643 add up to 23, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 91 steps to reach 1.
LaTeX source of the formulas on this page
\[ 55643 = 7 \times 7949 \]
55643 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 63600 |
| Euler totient φ(n) | 47688 |
| Square | 3096143449 |
| Cube | 172278709932707 |
| Square root | 235.887685 |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 91 |
| Scientific notation | 5.5643 × |
55643 in other forms
| Form | Value |
|---|---|
| In words | fifty-five thousand six hundred and forty-three |
| Binary (base 2) | 1101100101011011 |
| Octal (base 8) | 154533 |
| Hexadecimal (base 16) | D95B |
| Base 3 | 2211022212 |
| As time | 55643 seconds = 15 h 27 min 23 s |
Is 55643 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 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | 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 | Yes (55643 ÷ 7 = 7949) | 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 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 5) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 3) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 55643 a prime number?
No. 55643 = 7 × 7949, so it is divisible by 7.
What are the factors of 55643?
1, 7, 7949, 55643.
What is 55643 in binary?
1101100101011011 (hexadecimal D95B, octal 154533).
What is the square root of 55643?
About 235.8877.
Is 55643 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 55643?
55643 is a semiprime: 7 × 7949, the product of two primes.