The number 42551
42551 is a composite number with 4 divisors. Its prime factorisation is 17 × 2503. Divisors (4): 1, 17, 2503, 42551.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42551: a Harshad number: divisible by its digit sum 17; a semiprime: 17 × 2503, the product of two primes.
- 2
42551 is composite. Its prime factorisation is
- 3
The divisors add up to 45072; without 42551 itself that is 2521, so 42551 is deficient (2521 is less than 42551). Euler's totient φ(42551) = 40032 numbers up to 42551 share no factor with it.
- 4
The digits of 42551 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 150 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42551 = 17 \times 2503 \]
42551 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 45072 |
| Euler totient φ(n) | 40032 |
| Square | 1810587601 |
| Cube | 77042313010151 |
| Square root | 206.278937 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 150 |
| Scientific notation | 4.2551 × |
42551 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand five hundred and fifty-one |
| Binary (base 2) | 1010011000110111 |
| Octal (base 8) | 123067 |
| Hexadecimal (base 16) | A637 |
| Base 3 | 2011100222 |
| As time | 42551 seconds = 11 h 49 min 11 s |
Is 42551 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 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 1) | 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 | No (remainder 5) | 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 7) | 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 1) | 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 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 42551 a prime number?
No. 42551 = 17 × 2503, so it is divisible by 17.
What are the factors of 42551?
1, 17, 2503, 42551.
What is 42551 in binary?
1010011000110111 (hexadecimal A637, octal 123067).
What is the square root of 42551?
About 206.2789.
Is 42551 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 42551?
42551 is a Harshad number: divisible by its digit sum 17; a semiprime: 17 × 2503, the product of two primes.