The number 8438
8438 is a composite number with 4 divisors. Its prime factorisation is 2 × 4219. Divisors (4): 1, 2, 4219, 8438.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 8438: a semiprime: 2 × 4219, the product of two primes.
- 2
8438 is composite. Its prime factorisation is
- 3
The divisors add up to 12660; without 8438 itself that is 4222, so 8438 is deficient (4222 is less than 8438). Euler's totient φ(8438) = 4218 numbers up to 8438 share no factor with it.
- 4
The digits of 8438 add up to 23, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 158 steps to reach 1.
LaTeX source of the formulas on this page
\[ 8438 = 2 \times 4219 \]
8438 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 12660 |
| Euler totient φ(n) | 4218 |
| Square | 71199844 |
| Cube | 600784283672 |
| Square root | 91.858587 |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 158 |
| Scientific notation | 8.438 × |
8438 in other forms
| Form | Value |
|---|---|
| In words | eight thousand four hundred and thirty-eight |
| Binary (base 2) | 10000011110110 |
| Octal (base 8) | 20366 |
| Hexadecimal (base 16) | 20F6 |
| Base 3 | 102120112 |
| As time | 8438 seconds = 2 h 20 min 38 s |
Is 8438 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (8438 ÷ 2 = 4219) | 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 5) | 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 1) | 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 8438 a prime number?
No. 8438 = 2 × 4219, so it is divisible by 2.
What are the factors of 8438?
1, 2, 4219, 8438.
What is 8438 in binary?
10000011110110 (hexadecimal 20F6, octal 20366).
What is the square root of 8438?
About 91.8586.
Is 8438 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 8438?
8438 is a semiprime: 2 × 4219, the product of two primes.