The number 80625
80625 is a composite number with 20 divisors. Its prime factorisation is 3 × × 43. Divisors (20): 1, 3, 5, 15, 25, 43, 75, 125, 129, 215, 375, 625, 645, 1075, 1875, 3225 … 80625.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 80625: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
80625 is composite. Its prime factorisation is
- 3
The divisors add up to 137456; without 80625 itself that is 56831, so 80625 is deficient (56831 is less than 80625). Euler's totient φ(80625) = 42000 numbers up to 80625 share no factor with it.
- 4
The digits of 80625 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 89 steps to reach 1.
LaTeX source of the formulas on this page
\[ 80625 = 3 \times 5^{4} \times 43 \]80625 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 20 |
| Sum of divisors | 137456 |
| Euler totient φ(n) | 42000 |
| Square | 6500390625 |
| Cube | 524093994140625 |
| Square root | 283.945417 (= 25√129) |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 89 |
| Scientific notation | 8.0625 × |
80625 in other forms
| Form | Value |
|---|---|
| In words | eighty thousand six hundred and twenty-five |
| Binary (base 2) | 10011101011110001 |
| Octal (base 8) | 235361 |
| Hexadecimal (base 16) | 13AF1 |
| Base 3 | 11002121010 |
| As time | 80625 seconds = 22 h 23 min 45 s |
Is 80625 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (80625 ÷ 3 = 26875) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 1) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (80625 ÷ 5 = 16125) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 3) | 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 1) | 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 5) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 6) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 80625 a prime number?
No. 80625 = 3 × × 43, so it is divisible by 3.
What are the factors of 80625?
1, 3, 5, 15, 25, 43, 75, 125, 129, 215, 375, 625, 645, 1075, 1875, 3225, 5375, 16125, 26875, 80625.
What is 80625 in binary?
10011101011110001 (hexadecimal 13AF1, octal 235361).
What is the square root of 80625?
About 283.9454, exactly 25√129.
Is 80625 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 80625?
80625 is a happy number: repeatedly adding the squares of its digits reaches 1.