The number 4891
4891 is a composite number with 4 divisors. Its prime factorisation is 67 × 73. Divisors (4): 1, 67, 73, 4891.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 4891: a semiprime: 67 × 73, the product of two primes.
- 2
4891 is composite. Its prime factorisation is
- 3
The divisors add up to 5032; without 4891 itself that is 141, so 4891 is deficient (141 is less than 4891). Euler's totient φ(4891) = 4752 numbers up to 4891 share no factor with it.
- 4
The digits of 4891 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 178 steps to reach 1.
LaTeX source of the formulas on this page
\[ 4891 = 67 \times 73 \]
4891 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 5032 |
| Euler totient φ(n) | 4752 |
| Square | 23921881 |
| Cube | 117001919971 |
| Square root | 69.935685 |
| Digit sum / digital root | 22 / 4 |
| Collatz steps to 1 | 178 |
| Scientific notation | 4.891 × |
4891 in other forms
| Form | Value |
|---|---|
| In words | four thousand eight hundred and ninety-one |
| Binary (base 2) | 1001100011011 |
| Octal (base 8) | 11433 |
| Hexadecimal (base 16) | 131B |
| Base 3 | 20201011 |
| As time | 4891 seconds = 1 h 21 min 31 s |
Is 4891 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 3) | 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 3) | 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 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 4891 a prime number?
No. 4891 = 67 × 73, so it is divisible by 67.
What are the factors of 4891?
1, 67, 73, 4891.
What is 4891 in binary?
1001100011011 (hexadecimal 131B, octal 11433).
What is the square root of 4891?
About 69.9357.
Is 4891 divisible by 3?
No. Its digits add up to 22, which is not a multiple of 3.
What is special about the number 4891?
4891 is a semiprime: 67 × 73, the product of two primes.