The number 782
782 is a composite number with 8 divisors. Its prime factorisation is 2 × 17 × 23. Divisors (8): 1, 2, 17, 23, 34, 46, 391, 782.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 782: a Harshad number: divisible by its digit sum 17.
- 2
782 is composite. Its prime factorisation is
- 3
The divisors add up to 1296; without 782 itself that is 514, so 782 is deficient (514 is less than 782). Euler's totient φ(782) = 352 numbers up to 782 share no factor with it.
- 4
The digits of 782 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 121 steps to reach 1.
LaTeX source of the formulas on this page
\[ 782 = 2 \times 17 \times 23 \]
782 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 1296 |
| Euler totient φ(n) | 352 |
| Square | 611524 |
| Cube | 478211768 |
| Square root | 27.964263 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 121 |
| Scientific notation | 7.82 × |
782 in other forms
| Form | Value |
|---|---|
| In words | seven hundred and eighty-two |
| Roman numerals | DCCLXXXII |
| Binary (base 2) | 1100001110 |
| Octal (base 8) | 1416 |
| Hexadecimal (base 16) | 30E |
| Base 3 | 1001222 |
| As time | 782 seconds = 13 min 2 s |
Is 782 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (782 ÷ 2 = 391) | 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 2) | 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 5) | 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 8) | 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 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 782 a prime number?
No. 782 = 2 × 17 × 23, so it is divisible by 2.
What are the factors of 782?
1, 2, 17, 23, 34, 46, 391, 782.
What is 782 in binary?
1100001110 (hexadecimal 30E, octal 1416).
What is the square root of 782?
About 27.9643.
What is 782 in Roman numerals?
DCCLXXXII.
Is 782 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 782?
782 is a Harshad number: divisible by its digit sum 17.