The number 80742
80742 is a composite number with 8 divisors. Its prime factorisation is 2 × 3 × 13457. Divisors (8): 1, 2, 3, 6, 13457, 26914, 40371, 80742.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 80742: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
80742 is composite. Its prime factorisation is
- 3
The divisors add up to 161496; without 80742 itself that is 80754, so 80742 is abundant (80754 is more than 80742). Euler's totient φ(80742) = 26912 numbers up to 80742 share no factor with it.
- 4
The digits of 80742 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 138 steps to reach 1.
LaTeX source of the formulas on this page
\[ 80742 = 2 \times 3 \times 13457 \]
80742 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 161496 |
| Euler totient φ(n) | 26912 |
| Square | 6519270564 |
| Cube | 526378943878488 |
| Square root | 284.151368 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 138 |
| Scientific notation | 8.0742 × |
80742 in other forms
| Form | Value |
|---|---|
| In words | eighty thousand seven hundred and forty-two |
| Binary (base 2) | 10011101101100110 |
| Octal (base 8) | 235546 |
| Hexadecimal (base 16) | 13B66 |
| Base 3 | 11002202110 |
| As time | 80742 seconds = 22 h 25 min 42 s |
Is 80742 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (80742 ÷ 2 = 40371) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (80742 ÷ 3 = 26914) | 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 (80742 ÷ 6 = 13457) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 4) | 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 2) | 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 80742 a prime number?
No. 80742 = 2 × 3 × 13457, so it is divisible by 2.
What are the factors of 80742?
1, 2, 3, 6, 13457, 26914, 40371, 80742.
What is 80742 in binary?
10011101101100110 (hexadecimal 13B66, octal 235546).
What is the square root of 80742?
About 284.1514.
Is 80742 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 80742?
80742 is a happy number: repeatedly adding the squares of its digits reaches 1.