The number 55561
55561 is a composite number with 4 divisors. Its prime factorisation is 11 × 5051. Divisors (4): 1, 11, 5051, 55561.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 55561: a semiprime: 11 × 5051, the product of two primes.
- 2
55561 is composite. Its prime factorisation is
- 3
The divisors add up to 60624; without 55561 itself that is 5063, so 55561 is deficient (5063 is less than 55561). Euler's totient φ(55561) = 50500 numbers up to 55561 share no factor with it.
- 4
The digits of 55561 add up to 22, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 140 steps to reach 1.
LaTeX source of the formulas on this page
\[ 55561 = 11 \times 5051 \]
55561 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 60624 |
| Euler totient φ(n) | 50500 |
| Square | 3087024721 |
| Cube | 171518180523481 |
| Square root | 235.713810 |
| Digit sum / digital root | 22 / 4 |
| Collatz steps to 1 | 140 |
| Scientific notation | 5.5561 × |
55561 in other forms
| Form | Value |
|---|---|
| In words | fifty-five thousand five hundred and sixty-one |
| Binary (base 2) | 1101100100001001 |
| Octal (base 8) | 154411 |
| Hexadecimal (base 16) | D909 |
| Base 3 | 2211012211 |
| As time | 55561 seconds = 15 h 26 min 1 s |
Is 55561 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 2) | 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 4) | 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 | Yes (55561 ÷ 11 = 5051) | 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 55561 a prime number?
No. 55561 = 11 × 5051, so it is divisible by 11.
What are the factors of 55561?
1, 11, 5051, 55561.
What is 55561 in binary?
1101100100001001 (hexadecimal D909, octal 154411).
What is the square root of 55561?
About 235.7138.
Is 55561 divisible by 3?
No. Its digits add up to 22, which is not a multiple of 3.
What is special about the number 55561?
55561 is a semiprime: 11 × 5051, the product of two primes.