The number 7790
7790 is a composite number with 16 divisors. Its prime factorisation is 2 × 5 × 19 × 41. Divisors (16): 1, 2, 5, 10, 19, 38, 41, 82, 95, 190, 205, 410, 779, 1558, 3895, 7790.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
7790 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
7790 is composite. Its prime factorisation is
- 3
The divisors add up to 15120; without 7790 itself that is 7330, so 7790 is deficient (7330 is less than 7790). Euler's totient φ(7790) = 2880 numbers up to 7790 share no factor with it.
- 4
The digits of 7790 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 83 steps to reach 1.
LaTeX source of the formulas on this page
\[ 7790 = 2 \times 5 \times 19 \times 41 \]
7790 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 15120 |
| Euler totient φ(n) | 2880 |
| Square | 60684100 |
| Cube | 472729139000 |
| Square root | 88.260977 |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 83 |
| Scientific notation | 7.79 × |
7790 in other forms
| Form | Value |
|---|---|
| In words | seven thousand seven hundred and ninety |
| Binary (base 2) | 1111001101110 |
| Octal (base 8) | 17156 |
| Hexadecimal (base 16) | 1E6E |
| Base 3 | 101200112 |
| As time | 7790 seconds = 2 h 9 min 50 s |
Is 7790 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (7790 ÷ 2 = 3895) | 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 | Yes (7790 ÷ 5 = 1558) | 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 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 5) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (7790 ÷ 10 = 779) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 2) | 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 7790 a prime number?
No. 7790 = 2 × 5 × 19 × 41, so it is divisible by 2.
What are the factors of 7790?
1, 2, 5, 10, 19, 38, 41, 82, 95, 190, 205, 410, 779, 1558, 3895, 7790.
What is 7790 in binary?
1111001101110 (hexadecimal 1E6E, octal 17156).
What is the square root of 7790?
About 88.2610.
Is 7790 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 7790?
It is a composite number with 16 divisors.