The number 71216
71216 is a composite number with 10 divisors. Its prime factorisation is × 4451. Divisors (10): 1, 2, 4, 8, 16, 4451, 8902, 17804, 35608, 71216.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 71216: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
71216 is composite. Its prime factorisation is
- 3
The divisors add up to 138012; without 71216 itself that is 66796, so 71216 is deficient (66796 is less than 71216). Euler's totient φ(71216) = 35600 numbers up to 71216 share no factor with it.
- 4
The digits of 71216 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 143 steps to reach 1.
LaTeX source of the formulas on this page
\[ 71216 = 2^{4} \times 4451 \]71216 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 10 |
| Sum of divisors | 138012 |
| Euler totient φ(n) | 35600 |
| Square | 5071718656 |
| Cube | 361187515805696 |
| Square root | 266.863261 (= 4√4451) |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 143 |
| Scientific notation | 7.1216 × |
71216 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand two hundred and sixteen |
| Binary (base 2) | 10001011000110000 |
| Octal (base 8) | 213060 |
| Hexadecimal (base 16) | 11630 |
| Base 3 | 10121200122 |
| As time | 71216 seconds = 19 h 46 min 56 s |
Is 71216 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (71216 ÷ 2 = 35608) | 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 (71216 ÷ 4 = 17804) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 1) | 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 5) | 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 (71216 ÷ 8 = 8902) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 8) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 6) | 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 71216 a prime number?
No. 71216 = × 4451, so it is divisible by 2.
What are the factors of 71216?
1, 2, 4, 8, 16, 4451, 8902, 17804, 35608, 71216.
What is 71216 in binary?
10001011000110000 (hexadecimal 11630, octal 213060).
What is the square root of 71216?
About 266.8633, exactly 4√4451.
Is 71216 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 71216?
71216 is a happy number: repeatedly adding the squares of its digits reaches 1.