The number 10091
10091 is a twin prime (10091 and 10093 are both prime) and the 1238th prime number. Its only divisors are 1 and 10091.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 10091: a twin prime (10091 and 10093 are both prime); the 1238th prime number.
- 2
10091 is prime, so its only factors are 1 and 10091. It is the 1238th prime; the next prime is 10093 and the one before is 10079.
- 3
The divisors add up to 10092; without 10091 itself that is 1, so 10091 is deficient (1 is less than 10091). Euler's totient φ(10091) = 10090 numbers up to 10091 share no factor with it.
- 4
The digits of 10091 add up to 11, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 47 steps to reach 1.
10091 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 10092 |
| Euler totient φ(n) | 10090 |
| Square | 101828281 |
| Cube | 1027549183571 |
| Square root | 100.453970 |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 47 |
| Scientific notation | 1.0091 × |
10091 in other forms
| Form | Value |
|---|---|
| In words | ten thousand and ninety-one |
| Binary (base 2) | 10011101101011 |
| Octal (base 8) | 23553 |
| Hexadecimal (base 16) | 276B |
| Base 3 | 111211202 |
| As time | 10091 seconds = 2 h 48 min 11 s |
Is 10091 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 1) | 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 | No (remainder 4) | 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 2) | 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 4) | 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 10091 a prime number?
Yes. 10091 is divisible only by 1 and itself.
What are the factors of 10091?
1, 10091.
What is 10091 in binary?
10011101101011 (hexadecimal 276B, octal 23553).
What is the square root of 10091?
About 100.4540.
Is 10091 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 10091?
10091 is a twin prime (10091 and 10093 are both prime); the 1238th prime number.