The number 48991
48991 is a twin prime (48989 and 48991 are both prime) and the 5035th prime number. Its only divisors are 1 and 48991.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 48991: a twin prime (48989 and 48991 are both prime); the 5035th prime number.
- 2
48991 is prime, so its only factors are 1 and 48991. It is the 5035th prime; the next prime is 49003 and the one before is 48989.
- 3
The divisors add up to 48992; without 48991 itself that is 1, so 48991 is deficient (1 is less than 48991). Euler's totient φ(48991) = 48990 numbers up to 48991 share no factor with it.
- 4
The digits of 48991 add up to 31, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 65 steps to reach 1.
48991 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 48992 |
| Euler totient φ(n) | 48990 |
| Square | 2400118081 |
| Cube | 117584184906271 |
| Square root | 221.339106 |
| Digit sum / digital root | 31 / 4 |
| Collatz steps to 1 | 65 |
| Scientific notation | 4.8991 × |
48991 in other forms
| Form | Value |
|---|---|
| In words | forty-eight thousand nine hundred and ninety-one |
| Binary (base 2) | 1011111101011111 |
| Octal (base 8) | 137537 |
| Hexadecimal (base 16) | BF5F |
| Base 3 | 2111012111 |
| As time | 48991 seconds = 13 h 36 min 31 s |
Is 48991 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 7) | 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 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 48991 a prime number?
Yes. 48991 is divisible only by 1 and itself.
What are the factors of 48991?
1, 48991.
What is 48991 in binary?
1011111101011111 (hexadecimal BF5F, octal 137537).
What is the square root of 48991?
About 221.3391.
Is 48991 divisible by 3?
No. Its digits add up to 31, which is not a multiple of 3.
What is special about the number 48991?
48991 is a twin prime (48989 and 48991 are both prime); the 5035th prime number.