The number 42045
42045 is a composite number with 8 divisors. Its prime factorisation is 3 × 5 × 2803. Divisors (8): 1, 3, 5, 15, 2803, 8409, 14015, 42045.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42045: a Harshad number: divisible by its digit sum 15.
- 2
42045 is composite. Its prime factorisation is
- 3
The divisors add up to 67296; without 42045 itself that is 25251, so 42045 is deficient (25251 is less than 42045). Euler's totient φ(42045) = 22416 numbers up to 42045 share no factor with it.
- 4
The digits of 42045 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 88 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42045 = 3 \times 5 \times 2803 \]
42045 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 67296 |
| Euler totient φ(n) | 22416 |
| Square | 1767782025 |
| Cube | 74326395241125 |
| Square root | 205.048775 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 88 |
| Scientific notation | 4.2045 × |
42045 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand and forty-five |
| Binary (base 2) | 1010010000111101 |
| Octal (base 8) | 122075 |
| Hexadecimal (base 16) | A43D |
| Base 3 | 2010200020 |
| As time | 42045 seconds = 11 h 40 min 45 s |
Is 42045 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 (42045 ÷ 3 = 14015) | 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 | Yes (42045 ÷ 5 = 8409) | 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 | No (remainder 3) | 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 6) | 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 3) | 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 42045 a prime number?
No. 42045 = 3 × 5 × 2803, so it is divisible by 3.
What are the factors of 42045?
1, 3, 5, 15, 2803, 8409, 14015, 42045.
What is 42045 in binary?
1010010000111101 (hexadecimal A43D, octal 122075).
What is the square root of 42045?
About 205.0488.
Is 42045 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 42045?
42045 is a Harshad number: divisible by its digit sum 15.