The number 42109
42109 is a composite number with 4 divisors. Its prime factorisation is 17 × 2477. Divisors (4): 1, 17, 2477, 42109.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42109: a semiprime: 17 × 2477, the product of two primes.
- 2
42109 is composite. Its prime factorisation is
- 3
The divisors add up to 44604; without 42109 itself that is 2495, so 42109 is deficient (2495 is less than 42109). Euler's totient φ(42109) = 39616 numbers up to 42109 share no factor with it.
- 4
The digits of 42109 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 88 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42109 = 17 \times 2477 \]
42109 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 44604 |
| Euler totient φ(n) | 39616 |
| Square | 1773167881 |
| Cube | 74666326301029 |
| Square root | 205.204776 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 88 |
| Scientific notation | 4.2109 × |
42109 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand one hundred and nine |
| Binary (base 2) | 1010010001111101 |
| Octal (base 8) | 122175 |
| Hexadecimal (base 16) | A47D |
| Base 3 | 2010202121 |
| As time | 42109 seconds = 11 h 41 min 49 s |
Is 42109 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 4) | 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 4) | 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 5) | 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 9) | 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 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 42109 a prime number?
No. 42109 = 17 × 2477, so it is divisible by 17.
What are the factors of 42109?
1, 17, 2477, 42109.
What is 42109 in binary?
1010010001111101 (hexadecimal A47D, octal 122175).
What is the square root of 42109?
About 205.2048.
Is 42109 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 42109?
42109 is a semiprime: 17 × 2477, the product of two primes.