The number 42749
42749 is a composite number with 8 divisors. Its prime factorisation is 7 × 31 × 197. Divisors (8): 1, 7, 31, 197, 217, 1379, 6107, 42749.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
42749 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
42749 is composite. Its prime factorisation is
- 3
The divisors add up to 50688; without 42749 itself that is 7939, so 42749 is deficient (7939 is less than 42749). Euler's totient φ(42749) = 35280 numbers up to 42749 share no factor with it.
- 4
The digits of 42749 add up to 26, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 101 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42749 = 7 \times 31 \times 197 \]
42749 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 50688 |
| Euler totient φ(n) | 35280 |
| Square | 1827477001 |
| Cube | 78122814315749 |
| Square root | 206.758313 |
| Digit sum / digital root | 26 / 8 |
| Collatz steps to 1 | 101 |
| Scientific notation | 4.2749 × |
42749 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand seven hundred and forty-nine |
| Binary (base 2) | 1010011011111101 |
| Octal (base 8) | 123375 |
| Hexadecimal (base 16) | A6FD |
| Base 3 | 2011122022 |
| As time | 42749 seconds = 11 h 52 min 29 s |
Is 42749 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 2) | 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 5) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (42749 ÷ 7 = 6107) | 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 8) | 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 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 42749 a prime number?
No. 42749 = 7 × 31 × 197, so it is divisible by 7.
What are the factors of 42749?
1, 7, 31, 197, 217, 1379, 6107, 42749.
What is 42749 in binary?
1010011011111101 (hexadecimal A6FD, octal 123375).
What is the square root of 42749?
About 206.7583.
Is 42749 divisible by 3?
No. Its digits add up to 26, which is not a multiple of 3.
What is special about the number 42749?
It is a composite number with 8 divisors.