The number 424
424 is a palindrome: it reads 424 backwards too. Its prime factorisation is × 53. Divisors (8): 1, 2, 4, 8, 53, 106, 212, 424.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 424: a palindrome: it reads 424 backwards too.
- 2
424 is composite. Its prime factorisation is
- 3
The divisors add up to 810; without 424 itself that is 386, so 424 is deficient (386 is less than 424). Euler's totient φ(424) = 208 numbers up to 424 share no factor with it.
- 4
The digits of 424 add up to 10, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 14 steps to reach 1.
LaTeX source of the formulas on this page
\[ 424 = 2^{3} \times 53 \]424 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 810 |
| Euler totient φ(n) | 208 |
| Square | 179776 |
| Cube | 76225024 |
| Square root | 20.591260 (= 2√106) |
| Digit sum / digital root | 10 / 1 |
| Collatz steps to 1 | 14 |
| Scientific notation | 4.24 × |
424 in other forms
| Form | Value |
|---|---|
| In words | four hundred and twenty-four |
| Roman numerals | CDXXIV |
| Binary (base 2) | 110101000 |
| Octal (base 8) | 650 |
| Hexadecimal (base 16) | 1A8 |
| Base 3 | 120201 |
| As time | 424 seconds = 7 min 4 s |
Is 424 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (424 ÷ 2 = 212) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (424 ÷ 4 = 106) | 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 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 4) | 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 | Yes (424 ÷ 8 = 53) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 4) | 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 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 424 a prime number?
No. 424 = × 53, so it is divisible by 2.
What are the factors of 424?
1, 2, 4, 8, 53, 106, 212, 424.
What is 424 in binary?
110101000 (hexadecimal 1A8, octal 650).
What is the square root of 424?
About 20.5913, exactly 2√106.
What is 424 in Roman numerals?
CDXXIV.
Is 424 divisible by 3?
No. Its digits add up to 10, which is not a multiple of 3.
What is special about the number 424?
424 is a palindrome: it reads 424 backwards too.