The number 7142
7142 is a composite number with 4 divisors. Its prime factorisation is 2 × 3571. Divisors (4): 1, 2, 3571, 7142.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 7142: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 2 × 3571, the product of two primes.
- 2
7142 is composite. Its prime factorisation is
- 3
The divisors add up to 10716; without 7142 itself that is 3574, so 7142 is deficient (3574 is less than 7142). Euler's totient φ(7142) = 3570 numbers up to 7142 share no factor with it.
- 4
The digits of 7142 add up to 14, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 31 steps to reach 1.
LaTeX source of the formulas on this page
\[ 7142 = 2 \times 3571 \]
7142 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 10716 |
| Euler totient φ(n) | 3570 |
| Square | 51008164 |
| Cube | 364300307288 |
| Square root | 84.510354 |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 31 |
| Scientific notation | 7.142 × |
7142 in other forms
| Form | Value |
|---|---|
| In words | seven thousand one hundred and forty-two |
| Binary (base 2) | 1101111100110 |
| Octal (base 8) | 15746 |
| Hexadecimal (base 16) | 1BE6 |
| Base 3 | 100210112 |
| As time | 7142 seconds = 1 h 59 min 2 s |
Is 7142 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (7142 ÷ 2 = 3571) | 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 2) | 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 | No (remainder 2) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 3) | 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 7142 a prime number?
No. 7142 = 2 × 3571, so it is divisible by 2.
What are the factors of 7142?
1, 2, 3571, 7142.
What is 7142 in binary?
1101111100110 (hexadecimal 1BE6, octal 15746).
What is the square root of 7142?
About 84.5104.
Is 7142 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 7142?
7142 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 2 × 3571, the product of two primes.