The number 71480
71480 is a composite number with 16 divisors. Its prime factorisation is × 5 × 1787. Divisors (16): 1, 2, 4, 5, 8, 10, 20, 40, 1787, 3574, 7148, 8935, 14296, 17870, 35740, 71480.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 71480: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 20.
- 2
71480 is composite. Its prime factorisation is
- 3
The divisors add up to 160920; without 71480 itself that is 89440, so 71480 is abundant (89440 is more than 71480). Euler's totient φ(71480) = 28576 numbers up to 71480 share no factor with it.
- 4
The digits of 71480 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 112 steps to reach 1.
LaTeX source of the formulas on this page
\[ 71480 = 2^{3} \times 5 \times 1787 \]71480 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 160920 |
| Euler totient φ(n) | 28576 |
| Square | 5109390400 |
| Cube | 365219225792000 |
| Square root | 267.357439 (= 2√17870) |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 112 |
| Scientific notation | 7.148 × |
71480 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand four hundred and eighty |
| Binary (base 2) | 10001011100111000 |
| Octal (base 8) | 213470 |
| Hexadecimal (base 16) | 11738 |
| Base 3 | 10122001102 |
| As time | 71480 seconds = 19 h 51 min 20 s |
Is 71480 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (71480 ÷ 2 = 35740) | 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 | Yes (71480 ÷ 4 = 17870) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (71480 ÷ 5 = 14296) | 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 3) | 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 (71480 ÷ 8 = 8935) | 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 | Yes (71480 ÷ 10 = 7148) | 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 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 71480 a prime number?
No. 71480 = × 5 × 1787, so it is divisible by 2.
What are the factors of 71480?
1, 2, 4, 5, 8, 10, 20, 40, 1787, 3574, 7148, 8935, 14296, 17870, 35740, 71480.
What is 71480 in binary?
10001011100111000 (hexadecimal 11738, octal 213470).
What is the square root of 71480?
About 267.3574, exactly 2√17870.
Is 71480 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 71480?
71480 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 20.