The number 84121
84121 is the 8199th prime number. Its only divisors are 1 and 84121.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 84121: the 8199th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
84121 is prime, so its only factors are 1 and 84121. It is the 8199th prime; the next prime is 84127 and the one before is 84089.
- 3
The divisors add up to 84122; without 84121 itself that is 1, so 84121 is deficient (1 is less than 84121). Euler's totient φ(84121) = 84120 numbers up to 84121 share no factor with it.
- 4
The digits of 84121 add up to 16, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 89 steps to reach 1.
84121 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 84122 |
| Euler totient φ(n) | 84120 |
| Square | 7076342641 |
| Cube | 595269019303561 |
| Square root | 290.036205 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 89 |
| Scientific notation | 8.4121 × |
84121 in other forms
| Form | Value |
|---|---|
| In words | eighty-four thousand one hundred and twenty-one |
| Binary (base 2) | 10100100010011001 |
| Octal (base 8) | 244231 |
| Hexadecimal (base 16) | 14899 |
| Base 3 | 11021101121 |
| As time | 84121 seconds = 23 h 22 min 1 s |
Is 84121 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 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 1) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 2) | 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 7) | 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 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 84121 a prime number?
Yes. 84121 is divisible only by 1 and itself.
What are the factors of 84121?
1, 84121.
What is 84121 in binary?
10100100010011001 (hexadecimal 14899, octal 244231).
What is the square root of 84121?
About 290.0362.
Is 84121 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 84121?
84121 is the 8199th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.