The number 7742
7742 is a composite number with 12 divisors. Its prime factorisation is 2 × × 79. Divisors (12): 1, 2, 7, 14, 49, 79, 98, 158, 553, 1106, 3871, 7742.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
7742 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
7742 is composite. Its prime factorisation is
- 3
The divisors add up to 13680; without 7742 itself that is 5938, so 7742 is deficient (5938 is less than 7742). Euler's totient φ(7742) = 3276 numbers up to 7742 share no factor with it.
- 4
The digits of 7742 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 114 steps to reach 1.
LaTeX source of the formulas on this page
\[ 7742 = 2 \times 7^{2} \times 79 \]7742 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 13680 |
| Euler totient φ(n) | 3276 |
| Square | 59938564 |
| Cube | 464044362488 |
| Square root | 87.988636 (= 7√158) |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 114 |
| Scientific notation | 7.742 × |
7742 in other forms
| Form | Value |
|---|---|
| In words | seven thousand seven hundred and forty-two |
| Binary (base 2) | 1111000111110 |
| Octal (base 8) | 17076 |
| Hexadecimal (base 16) | 1E3E |
| Base 3 | 101121202 |
| As time | 7742 seconds = 2 h 9 min 2 s |
Is 7742 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (7742 ÷ 2 = 3871) | 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 | Yes (7742 ÷ 7 = 1106) | 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 2) | 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 9) | 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 7742 a prime number?
No. 7742 = 2 × × 79, so it is divisible by 2.
What are the factors of 7742?
1, 2, 7, 14, 49, 79, 98, 158, 553, 1106, 3871, 7742.
What is 7742 in binary?
1111000111110 (hexadecimal 1E3E, octal 17076).
What is the square root of 7742?
About 87.9886, exactly 7√158.
Is 7742 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 7742?
It is a composite number with 12 divisors.