The number 42345
42345 is a composite number with 12 divisors. Its prime factorisation is × 5 × 941. Divisors (12): 1, 3, 5, 9, 15, 45, 941, 2823, 4705, 8469, 14115, 42345.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42345: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
42345 is composite. Its prime factorisation is
- 3
The divisors add up to 73476; without 42345 itself that is 31131, so 42345 is deficient (31131 is less than 42345). Euler's totient φ(42345) = 22560 numbers up to 42345 share no factor with it.
- 4
The digits of 42345 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 150 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42345 = 3^{2} \times 5 \times 941 \]42345 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 73476 |
| Euler totient φ(n) | 22560 |
| Square | 1793099025 |
| Cube | 75928778213625 |
| Square root | 205.779008 (= 3√4705) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 150 |
| Scientific notation | 4.2345 × |
42345 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand three hundred and forty-five |
| Binary (base 2) | 1010010101101001 |
| Octal (base 8) | 122551 |
| Hexadecimal (base 16) | A569 |
| Base 3 | 2011002100 |
| As time | 42345 seconds = 11 h 45 min 45 s |
Is 42345 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 (42345 ÷ 3 = 14115) | 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 (42345 ÷ 5 = 8469) | 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 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 1) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (42345 ÷ 9 = 4705) | 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 6) | 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 42345 a prime number?
No. 42345 = × 5 × 941, so it is divisible by 3.
What are the factors of 42345?
1, 3, 5, 9, 15, 45, 941, 2823, 4705, 8469, 14115, 42345.
What is 42345 in binary?
1010010101101001 (hexadecimal A569, octal 122551).
What is the square root of 42345?
About 205.7790, exactly 3√4705.
Is 42345 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 42345?
42345 is a happy number: repeatedly adding the squares of its digits reaches 1.