The number 55921
55921 is the 5676th prime number. Its only divisors are 1 and 55921.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 55921: the 5676th prime number.
- 2
55921 is prime, so its only factors are 1 and 55921. It is the 5676th prime; the next prime is 55927 and the one before is 55903.
- 3
The divisors add up to 55922; without 55921 itself that is 1, so 55921 is deficient (1 is less than 55921). Euler's totient φ(55921) = 55920 numbers up to 55921 share no factor with it.
- 4
The digits of 55921 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 153 steps to reach 1.
55921 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 55922 |
| Euler totient φ(n) | 55920 |
| Square | 3127158241 |
| Cube | 174873815994961 |
| Square root | 236.476214 |
| Digit sum / digital root | 22 / 4 |
| Collatz steps to 1 | 153 |
| Scientific notation | 5.5921 × |
55921 in other forms
| Form | Value |
|---|---|
| In words | fifty-five thousand nine hundred and twenty-one |
| Binary (base 2) | 1101101001110001 |
| Octal (base 8) | 155161 |
| Hexadecimal (base 16) | DA71 |
| Base 3 | 2211201011 |
| As time | 55921 seconds = 15 h 32 min 1 s |
Is 55921 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 5) | 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 | No (remainder 8) | 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 55921 a prime number?
Yes. 55921 is divisible only by 1 and itself.
What are the factors of 55921?
1, 55921.
What is 55921 in binary?
1101101001110001 (hexadecimal DA71, octal 155161).
What is the square root of 55921?
About 236.4762.
Is 55921 divisible by 3?
No. Its digits add up to 22, which is not a multiple of 3.
What is special about the number 55921?
55921 is the 5676th prime number.