The number 25121
25121 is the 2773rd prime number. Its only divisors are 1 and 25121.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 25121: the 2773rd prime number.
- 2
25121 is prime, so its only factors are 1 and 25121. It is the 2773rd prime; the next prime is 25127 and the one before is 25117.
- 3
The divisors add up to 25122; without 25121 itself that is 1, so 25121 is deficient (1 is less than 25121). Euler's totient φ(25121) = 25120 numbers up to 25121 share no factor with it.
- 4
The digits of 25121 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 108 steps to reach 1.
25121 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 25122 |
| Euler totient φ(n) | 25120 |
| Square | 631064641 |
| Cube | 15852974846561 |
| Square root | 158.496057 |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 108 |
| Scientific notation | 2.5121 × |
25121 in other forms
| Form | Value |
|---|---|
| In words | twenty-five thousand one hundred and twenty-one |
| Binary (base 2) | 110001000100001 |
| Octal (base 8) | 61041 |
| Hexadecimal (base 16) | 6221 |
| Base 3 | 1021110102 |
| As time | 25121 seconds = 6 h 58 min 41 s |
Is 25121 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 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 5) | 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 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 8) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 25121 a prime number?
Yes. 25121 is divisible only by 1 and itself.
What are the factors of 25121?
1, 25121.
What is 25121 in binary?
110001000100001 (hexadecimal 6221, octal 61041).
What is the square root of 25121?
About 158.4961.
Is 25121 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 25121?
25121 is the 2773rd prime number.