The number 8080
8080 is a composite number with 20 divisors. Its prime factorisation is × 5 × 101. Divisors (20): 1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 101, 202, 404, 505, 808, 1010 … 8080.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 8080: a Harshad number: divisible by its digit sum 16.
- 2
8080 is composite. Its prime factorisation is
- 3
The divisors add up to 18972; without 8080 itself that is 10892, so 8080 is abundant (10892 is more than 8080). Euler's totient φ(8080) = 3200 numbers up to 8080 share no factor with it.
- 4
The digits of 8080 add up to 16, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 65 steps to reach 1.
LaTeX source of the formulas on this page
\[ 8080 = 2^{4} \times 5 \times 101 \]8080 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 20 |
| Sum of divisors | 18972 |
| Euler totient φ(n) | 3200 |
| Square | 65286400 |
| Cube | 527514112000 |
| Square root | 89.888820 (= 4√505) |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 65 |
| Scientific notation | 8.08 × |
8080 in other forms
| Form | Value |
|---|---|
| In words | eight thousand and eighty |
| Binary (base 2) | 1111110010000 |
| Octal (base 8) | 17620 |
| Hexadecimal (base 16) | 1F90 |
| Base 3 | 102002021 |
| As time | 8080 seconds = 2 h 14 min 40 s |
Is 8080 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (8080 ÷ 2 = 4040) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (8080 ÷ 4 = 2020) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (8080 ÷ 5 = 1616) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | 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 | Yes (8080 ÷ 8 = 1010) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (8080 ÷ 10 = 808) | 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 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 8080 a prime number?
No. 8080 = × 5 × 101, so it is divisible by 2.
What are the factors of 8080?
1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 101, 202, 404, 505, 808, 1010, 1616, 2020, 4040, 8080.
What is 8080 in binary?
1111110010000 (hexadecimal 1F90, octal 17620).
What is the square root of 8080?
About 89.8888, exactly 4√505.
Is 8080 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 8080?
8080 is a Harshad number: divisible by its digit sum 16.