The number 67121
67121 is the 6686th prime number. Its only divisors are 1 and 67121.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 67121: the 6686th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
67121 is prime, so its only factors are 1 and 67121. It is the 6686th prime; the next prime is 67129 and the one before is 67103.
- 3
The divisors add up to 67122; without 67121 itself that is 1, so 67121 is deficient (1 is less than 67121). Euler's totient φ(67121) = 67120 numbers up to 67121 share no factor with it.
- 4
The digits of 67121 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 112 steps to reach 1.
67121 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 67122 |
| Euler totient φ(n) | 67120 |
| Square | 4505228641 |
| Cube | 302395451612561 |
| Square root | 259.077209 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 112 |
| Scientific notation | 6.7121 × |
67121 in other forms
| Form | Value |
|---|---|
| In words | sixty-seven thousand one hundred and twenty-one |
| Binary (base 2) | 10000011000110001 |
| Octal (base 8) | 203061 |
| Hexadecimal (base 16) | 10631 |
| Base 3 | 10102001222 |
| As time | 67121 seconds = 18 h 38 min 41 s |
Is 67121 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 8) | 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 10) | 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 67121 a prime number?
Yes. 67121 is divisible only by 1 and itself.
What are the factors of 67121?
1, 67121.
What is 67121 in binary?
10000011000110001 (hexadecimal 10631, octal 203061).
What is the square root of 67121?
About 259.0772.
Is 67121 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 67121?
67121 is the 6686th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.