The number 42878
42878 is a composite number with 8 divisors. Its prime factorisation is 2 × 11 × 1949. Divisors (8): 1, 2, 11, 22, 1949, 3898, 21439, 42878.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
42878 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
42878 is composite. Its prime factorisation is
- 3
The divisors add up to 70200; without 42878 itself that is 27322, so 42878 is deficient (27322 is less than 42878). Euler's totient φ(42878) = 19480 numbers up to 42878 share no factor with it.
- 4
The digits of 42878 add up to 29, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 75 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42878 = 2 \times 11 \times 1949 \]
42878 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 70200 |
| Euler totient φ(n) | 19480 |
| Square | 1838522884 |
| Cube | 78832184220152 |
| Square root | 207.070036 |
| Digit sum / digital root | 29 / 2 |
| Collatz steps to 1 | 75 |
| Scientific notation | 4.2878 × |
42878 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand eight hundred and seventy-eight |
| Binary (base 2) | 1010011101111110 |
| Octal (base 8) | 123576 |
| Hexadecimal (base 16) | A77E |
| Base 3 | 2011211002 |
| As time | 42878 seconds = 11 h 54 min 38 s |
Is 42878 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (42878 ÷ 2 = 21439) | 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 | No (remainder 3) | 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 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 6) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 8) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (42878 ÷ 11 = 3898) | 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 42878 a prime number?
No. 42878 = 2 × 11 × 1949, so it is divisible by 2.
What are the factors of 42878?
1, 2, 11, 22, 1949, 3898, 21439, 42878.
What is 42878 in binary?
1010011101111110 (hexadecimal A77E, octal 123576).
What is the square root of 42878?
About 207.0700.
Is 42878 divisible by 3?
No. Its digits add up to 29, which is not a multiple of 3.
What is special about the number 42878?
It is a composite number with 8 divisors.