The number 15742
15742 is a composite number with 8 divisors. Its prime factorisation is 2 × 17 × 463. Divisors (8): 1, 2, 17, 34, 463, 926, 7871, 15742.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
15742 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
15742 is composite. Its prime factorisation is
- 3
The divisors add up to 25056; without 15742 itself that is 9314, so 15742 is deficient (9314 is less than 15742). Euler's totient φ(15742) = 7392 numbers up to 15742 share no factor with it.
- 4
The digits of 15742 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 84 steps to reach 1.
LaTeX source of the formulas on this page
\[ 15742 = 2 \times 17 \times 463 \]
15742 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 25056 |
| Euler totient φ(n) | 7392 |
| Square | 247810564 |
| Cube | 3901033898488 |
| Square root | 125.467127 |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 84 |
| Scientific notation | 1.5742 × |
15742 in other forms
| Form | Value |
|---|---|
| In words | fifteen thousand seven hundred and forty-two |
| Binary (base 2) | 11110101111110 |
| Octal (base 8) | 36576 |
| Hexadecimal (base 16) | 3D7E |
| Base 3 | 210121001 |
| As time | 15742 seconds = 4 h 22 min 22 s |
Is 15742 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (15742 ÷ 2 = 7871) | 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 | No (remainder 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 2) | 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 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 6) | 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 2) | 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 10) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 15742 a prime number?
No. 15742 = 2 × 17 × 463, so it is divisible by 2.
What are the factors of 15742?
1, 2, 17, 34, 463, 926, 7871, 15742.
What is 15742 in binary?
11110101111110 (hexadecimal 3D7E, octal 36576).
What is the square root of 15742?
About 125.4671.
Is 15742 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 15742?
It is a composite number with 8 divisors.