The number 42170
42170 is a composite number with 8 divisors. Its prime factorisation is 2 × 5 × 4217. Divisors (8): 1, 2, 5, 10, 4217, 8434, 21085, 42170.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42170: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
42170 is composite. Its prime factorisation is
- 3
The divisors add up to 75924; without 42170 itself that is 33754, so 42170 is deficient (33754 is less than 42170). Euler's totient φ(42170) = 16864 numbers up to 42170 share no factor with it.
- 4
The digits of 42170 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 57 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42170 = 2 \times 5 \times 4217 \]
42170 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 75924 |
| Euler totient φ(n) | 16864 |
| Square | 1778308900 |
| Cube | 74991286313000 |
| Square root | 205.353354 |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 57 |
| Scientific notation | 4.217 × |
42170 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand one hundred and seventy |
| Binary (base 2) | 1010010010111010 |
| Octal (base 8) | 122272 |
| Hexadecimal (base 16) | A4BA |
| Base 3 | 2010211212 |
| As time | 42170 seconds = 11 h 42 min 50 s |
Is 42170 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (42170 ÷ 2 = 21085) | 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 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (42170 ÷ 5 = 8434) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 2) | 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 2) | 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 | Yes (42170 ÷ 10 = 4217) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 42170 a prime number?
No. 42170 = 2 × 5 × 4217, so it is divisible by 2.
What are the factors of 42170?
1, 2, 5, 10, 4217, 8434, 21085, 42170.
What is 42170 in binary?
1010010010111010 (hexadecimal A4BA, octal 122272).
What is the square root of 42170?
About 205.3534.
Is 42170 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 42170?
42170 is a happy number: repeatedly adding the squares of its digits reaches 1.