The number 86121
86121 is a composite number with 12 divisors. Its prime factorisation is × 7 × 1367. Divisors (12): 1, 3, 7, 9, 21, 63, 1367, 4101, 9569, 12303, 28707, 86121.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
86121 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
86121 is composite. Its prime factorisation is
- 3
The divisors add up to 142272; without 86121 itself that is 56151, so 86121 is deficient (56151 is less than 86121). Euler's totient φ(86121) = 49176 numbers up to 86121 share no factor with it.
- 4
The digits of 86121 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 76 steps to reach 1.
LaTeX source of the formulas on this page
\[ 86121 = 3^{2} \times 7 \times 1367 \]86121 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 142272 |
| Euler totient φ(n) | 49176 |
| Square | 7416826641 |
| Cube | 638744527149561 |
| Square root | 293.463797 (= 3√9569) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 76 |
| Scientific notation | 8.6121 × |
86121 in other forms
| Form | Value |
|---|---|
| In words | eighty-six thousand one hundred and twenty-one |
| Binary (base 2) | 10101000001101001 |
| Octal (base 8) | 250151 |
| Hexadecimal (base 16) | 15069 |
| Base 3 | 11101010200 |
| As time | 86121 seconds = 23 h 55 min 21 s |
Is 86121 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 | Yes (86121 ÷ 3 = 28707) | 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 3) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (86121 ÷ 7 = 12303) | 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 | Yes (86121 ÷ 9 = 9569) | 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 2) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 86121 a prime number?
No. 86121 = × 7 × 1367, so it is divisible by 3.
What are the factors of 86121?
1, 3, 7, 9, 21, 63, 1367, 4101, 9569, 12303, 28707, 86121.
What is 86121 in binary?
10101000001101001 (hexadecimal 15069, octal 250151).
What is the square root of 86121?
About 293.4638, exactly 3√9569.
Is 86121 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 86121?
It is a composite number with 12 divisors.