The number 15438
15438 is a composite number with 16 divisors. Its prime factorisation is 2 × 3 × 31 × 83. Divisors (16): 1, 2, 3, 6, 31, 62, 83, 93, 166, 186, 249, 498, 2573, 5146, 7719, 15438.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
15438 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
15438 is composite. Its prime factorisation is
- 3
The divisors add up to 32256; without 15438 itself that is 16818, so 15438 is abundant (16818 is more than 15438). Euler's totient φ(15438) = 4920 numbers up to 15438 share no factor with it.
- 4
The digits of 15438 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 53 steps to reach 1.
LaTeX source of the formulas on this page
\[ 15438 = 2 \times 3 \times 31 \times 83 \]
15438 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 32256 |
| Euler totient φ(n) | 4920 |
| Square | 238331844 |
| Cube | 3679367007672 |
| Square root | 124.249748 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 53 |
| Scientific notation | 1.5438 × |
15438 in other forms
| Form | Value |
|---|---|
| In words | fifteen thousand four hundred and thirty-eight |
| Binary (base 2) | 11110001001110 |
| Octal (base 8) | 36116 |
| Hexadecimal (base 16) | 3C4E |
| Base 3 | 210011210 |
| As time | 15438 seconds = 4 h 17 min 18 s |
Is 15438 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (15438 ÷ 2 = 7719) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (15438 ÷ 3 = 5146) | 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 | Yes (15438 ÷ 6 = 2573) | 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 3) | 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 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 6) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 15438 a prime number?
No. 15438 = 2 × 3 × 31 × 83, so it is divisible by 2.
What are the factors of 15438?
1, 2, 3, 6, 31, 62, 83, 93, 166, 186, 249, 498, 2573, 5146, 7719, 15438.
What is 15438 in binary?
11110001001110 (hexadecimal 3C4E, octal 36116).
What is the square root of 15438?
About 124.2497.
Is 15438 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 15438?
It is a composite number with 16 divisors.