The number 55981
55981 is a composite number with 8 divisors. Its prime factorisation is 17 × 37 × 89. Divisors (8): 1, 17, 37, 89, 629, 1513, 3293, 55981.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
55981 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
55981 is composite. Its prime factorisation is
- 3
The divisors add up to 61560; without 55981 itself that is 5579, so 55981 is deficient (5579 is less than 55981). Euler's totient φ(55981) = 50688 numbers up to 55981 share no factor with it.
- 4
The digits of 55981 add up to 28, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 122 steps to reach 1.
LaTeX source of the formulas on this page
\[ 55981 = 17 \times 37 \times 89 \]
55981 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 61560 |
| Euler totient φ(n) | 50688 |
| Square | 3133872361 |
| Cube | 175437308641141 |
| Square root | 236.603043 |
| Digit sum / digital root | 28 / 1 |
| Collatz steps to 1 | 122 |
| Scientific notation | 5.5981 × |
55981 in other forms
| Form | Value |
|---|---|
| In words | fifty-five thousand nine hundred and eighty-one |
| Binary (base 2) | 1101101010101101 |
| Octal (base 8) | 155255 |
| Hexadecimal (base 16) | DAAD |
| Base 3 | 2211210101 |
| As time | 55981 seconds = 15 h 33 min 1 s |
Is 55981 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | 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 2) | 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 55981 a prime number?
No. 55981 = 17 × 37 × 89, so it is divisible by 17.
What are the factors of 55981?
1, 17, 37, 89, 629, 1513, 3293, 55981.
What is 55981 in binary?
1101101010101101 (hexadecimal DAAD, octal 155255).
What is the square root of 55981?
About 236.6030.
Is 55981 divisible by 3?
No. Its digits add up to 28, which is not a multiple of 3.
What is special about the number 55981?
It is a composite number with 8 divisors.