The number 42215
42215 is a composite number with 4 divisors. Its prime factorisation is 5 × 8443. Divisors (4): 1, 5, 8443, 42215.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42215: a semiprime: 5 × 8443, the product of two primes.
- 2
42215 is composite. Its prime factorisation is
- 3
The divisors add up to 50664; without 42215 itself that is 8449, so 42215 is deficient (8449 is less than 42215). Euler's totient φ(42215) = 33768 numbers up to 42215 share no factor with it.
- 4
The digits of 42215 add up to 14, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 80 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42215 = 5 \times 8443 \]
42215 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 50664 |
| Euler totient φ(n) | 33768 |
| Square | 1782106225 |
| Cube | 75231614288375 |
| Square root | 205.462892 |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 80 |
| Scientific notation | 4.2215 × |
42215 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand two hundred and fifteen |
| Binary (base 2) | 1010010011100111 |
| Octal (base 8) | 122347 |
| Hexadecimal (base 16) | A4E7 |
| Base 3 | 2010220112 |
| As time | 42215 seconds = 11 h 43 min 35 s |
Is 42215 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 | Yes (42215 ÷ 5 = 8443) | 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 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 5) | 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 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 42215 a prime number?
No. 42215 = 5 × 8443, so it is divisible by 5.
What are the factors of 42215?
1, 5, 8443, 42215.
What is 42215 in binary?
1010010011100111 (hexadecimal A4E7, octal 122347).
What is the square root of 42215?
About 205.4629.
Is 42215 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 42215?
42215 is a semiprime: 5 × 8443, the product of two primes.