The number 71123
71123 is a composite number with 4 divisors. Its prime factorisation is 13 × 5471. Divisors (4): 1, 13, 5471, 71123.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 71123: a semiprime: 13 × 5471, the product of two primes.
- 2
71123 is composite. Its prime factorisation is
- 3
The divisors add up to 76608; without 71123 itself that is 5485, so 71123 is deficient (5485 is less than 71123). Euler's totient φ(71123) = 65640 numbers up to 71123 share no factor with it.
- 4
The digits of 71123 add up to 14, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 81 steps to reach 1.
LaTeX source of the formulas on this page
\[ 71123 = 13 \times 5471 \]
71123 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 76608 |
| Euler totient φ(n) | 65640 |
| Square | 5058481129 |
| Cube | 359774353337867 |
| Square root | 266.688957 |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 81 |
| Scientific notation | 7.1123 × |
71123 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand one hundred and twenty-three |
| Binary (base 2) | 10001010111010011 |
| Octal (base 8) | 212723 |
| Hexadecimal (base 16) | 115D3 |
| Base 3 | 10121120012 |
| As time | 71123 seconds = 19 h 45 min 23 s |
Is 71123 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 | No (remainder 2) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 5) | 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 | No (remainder 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 5) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 3) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 8) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 71123 a prime number?
No. 71123 = 13 × 5471, so it is divisible by 13.
What are the factors of 71123?
1, 13, 5471, 71123.
What is 71123 in binary?
10001010111010011 (hexadecimal 115D3, octal 212723).
What is the square root of 71123?
About 266.6890.
Is 71123 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 71123?
71123 is a semiprime: 13 × 5471, the product of two primes.