The number 71481
71481 is a composite number with 4 divisors. Its prime factorisation is 3 × 23827. Divisors (4): 1, 3, 23827, 71481.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 71481: a semiprime: 3 × 23827, the product of two primes.
- 2
71481 is composite. Its prime factorisation is
- 3
The divisors add up to 95312; without 71481 itself that is 23831, so 71481 is deficient (23831 is less than 71481). Euler's totient φ(71481) = 47652 numbers up to 71481 share no factor with it.
- 4
The digits of 71481 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 125 steps to reach 1.
LaTeX source of the formulas on this page
\[ 71481 = 3 \times 23827 \]
71481 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 95312 |
| Euler totient φ(n) | 47652 |
| Square | 5109533361 |
| Cube | 365234554177641 |
| Square root | 267.359309 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 125 |
| Scientific notation | 7.1481 × |
71481 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand four hundred and eighty-one |
| Binary (base 2) | 10001011100111001 |
| Octal (base 8) | 213471 |
| Hexadecimal (base 16) | 11739 |
| Base 3 | 10122001110 |
| As time | 71481 seconds = 19 h 51 min 21 s |
Is 71481 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 (71481 ÷ 3 = 23827) | 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 | No (remainder 1) | 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 4) | 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 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 3) | 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 71481 a prime number?
No. 71481 = 3 × 23827, so it is divisible by 3.
What are the factors of 71481?
1, 3, 23827, 71481.
What is 71481 in binary?
10001011100111001 (hexadecimal 11739, octal 213471).
What is the square root of 71481?
About 267.3593.
Is 71481 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 71481?
71481 is a semiprime: 3 × 23827, the product of two primes.