The number 51428
51428 is a composite number with 24 divisors. Its prime factorisation is × 13 × 23 × 43. Divisors (24): 1, 2, 4, 13, 23, 26, 43, 46, 52, 86, 92, 172, 299, 559, 598, 989 … 51428.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
51428 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
51428 is composite. Its prime factorisation is
- 3
The divisors add up to 103488; without 51428 itself that is 52060, so 51428 is abundant (52060 is more than 51428). Euler's totient φ(51428) = 22176 numbers up to 51428 share no factor with it.
- 4
The digits of 51428 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 171 steps to reach 1.
LaTeX source of the formulas on this page
\[ 51428 = 2^{2} \times 13 \times 23 \times 43 \]51428 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 103488 |
| Euler totient φ(n) | 22176 |
| Square | 2644839184 |
| Cube | 136018789554752 |
| Square root | 226.777424 (= 2√12857) |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 171 |
| Scientific notation | 5.1428 × |
51428 in other forms
| Form | Value |
|---|---|
| In words | fifty-one thousand four hundred and twenty-eight |
| Binary (base 2) | 1100100011100100 |
| Octal (base 8) | 144344 |
| Hexadecimal (base 16) | C8E4 |
| Base 3 | 2121112202 |
| As time | 51428 seconds = 14 h 17 min 8 s |
Is 51428 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (51428 ÷ 2 = 25714) | 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 | Yes (51428 ÷ 4 = 12857) | 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 6) | 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 4) | 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 | No (remainder 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 51428 a prime number?
No. 51428 = × 13 × 23 × 43, so it is divisible by 2.
What are the factors of 51428?
1, 2, 4, 13, 23, 26, 43, 46, 52, 86, 92, 172, 299, 559, 598, 989, 1118, 1196, 1978, 2236, 3956, 12857, 25714, 51428.
What is 51428 in binary?
1100100011100100 (hexadecimal C8E4, octal 144344).
What is the square root of 51428?
About 226.7774, exactly 2√12857.
Is 51428 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 51428?
It is a composite number with 24 divisors.