The number 87143
87143 is a composite number with 8 divisors. Its prime factorisation is 7 × 59 × 211. Divisors (8): 1, 7, 59, 211, 413, 1477, 12449, 87143.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 87143: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
87143 is composite. Its prime factorisation is
- 3
The divisors add up to 101760; without 87143 itself that is 14617, so 87143 is deficient (14617 is less than 87143). Euler's totient φ(87143) = 73080 numbers up to 87143 share no factor with it.
- 4
The digits of 87143 add up to 23, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 195 steps to reach 1.
LaTeX source of the formulas on this page
\[ 87143 = 7 \times 59 \times 211 \]
87143 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 101760 |
| Euler totient φ(n) | 73080 |
| Square | 7593902449 |
| Cube | 661755441113207 |
| Square root | 295.199932 |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 195 |
| Scientific notation | 8.7143 × |
87143 in other forms
| Form | Value |
|---|---|
| In words | eighty-seven thousand one hundred and forty-three |
| Binary (base 2) | 10101010001100111 |
| Octal (base 8) | 252147 |
| Hexadecimal (base 16) | 15467 |
| Base 3 | 11102112112 |
| As time | 87143 seconds = 24 h 12 min 23 s |
Is 87143 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 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | 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 | Yes (87143 ÷ 7 = 12449) | 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 5) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 3) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 1) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 87143 a prime number?
No. 87143 = 7 × 59 × 211, so it is divisible by 7.
What are the factors of 87143?
1, 7, 59, 211, 413, 1477, 12449, 87143.
What is 87143 in binary?
10101010001100111 (hexadecimal 15467, octal 252147).
What is the square root of 87143?
About 295.1999.
Is 87143 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 87143?
87143 is a happy number: repeatedly adding the squares of its digits reaches 1.