The number 40782
40782 is a composite number with 16 divisors. Its prime factorisation is 2 × 3 × 7 × 971. Divisors (16): 1, 2, 3, 6, 7, 14, 21, 42, 971, 1942, 2913, 5826, 6797, 13594, 20391, 40782.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 40782: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 21.
- 2
40782 is composite. Its prime factorisation is
- 3
The divisors add up to 93312; without 40782 itself that is 52530, so 40782 is abundant (52530 is more than 40782). Euler's totient φ(40782) = 11640 numbers up to 40782 share no factor with it.
- 4
The digits of 40782 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 137 steps to reach 1.
LaTeX source of the formulas on this page
\[ 40782 = 2 \times 3 \times 7 \times 971 \]
40782 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 93312 |
| Euler totient φ(n) | 11640 |
| Square | 1663171524 |
| Cube | 67827461091768 |
| Square root | 201.945537 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 137 |
| Scientific notation | 4.0782 × |
40782 in other forms
| Form | Value |
|---|---|
| In words | forty thousand seven hundred and eighty-two |
| Binary (base 2) | 1001111101001110 |
| Octal (base 8) | 117516 |
| Hexadecimal (base 16) | 9F4E |
| Base 3 | 2001221110 |
| As time | 40782 seconds = 11 h 19 min 42 s |
Is 40782 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (40782 ÷ 2 = 20391) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (40782 ÷ 3 = 13594) | 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 | Yes (40782 ÷ 6 = 6797) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (40782 ÷ 7 = 5826) | 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 2) | 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 40782 a prime number?
No. 40782 = 2 × 3 × 7 × 971, so it is divisible by 2.
What are the factors of 40782?
1, 2, 3, 6, 7, 14, 21, 42, 971, 1942, 2913, 5826, 6797, 13594, 20391, 40782.
What is 40782 in binary?
1001111101001110 (hexadecimal 9F4E, octal 117516).
What is the square root of 40782?
About 201.9455.
Is 40782 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 40782?
40782 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 21.