The number 71724
71724 is a composite number with 24 divisors. Its prime factorisation is × 3 × 43 × 139. Divisors (24): 1, 2, 3, 4, 6, 12, 43, 86, 129, 139, 172, 258, 278, 417, 516, 556 … 71724.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
71724 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
71724 is composite. Its prime factorisation is
- 3
The divisors add up to 172480; without 71724 itself that is 100756, so 71724 is abundant (100756 is more than 71724). Euler's totient φ(71724) = 23184 numbers up to 71724 share no factor with it.
- 4
The digits of 71724 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 50 steps to reach 1.
LaTeX source of the formulas on this page
\[ 71724 = 2^{2} \times 3 \times 43 \times 139 \]71724 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 172480 |
| Euler totient φ(n) | 23184 |
| Square | 5144332176 |
| Cube | 368972080991424 |
| Square root | 267.813368 (= 2√17931) |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 50 |
| Scientific notation | 7.1724 × |
71724 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand seven hundred and twenty-four |
| Binary (base 2) | 10001100000101100 |
| Octal (base 8) | 214054 |
| Hexadecimal (base 16) | 1182C |
| Base 3 | 10122101110 |
| As time | 71724 seconds = 19 h 55 min 24 s |
Is 71724 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (71724 ÷ 2 = 35862) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (71724 ÷ 3 = 23908) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (71724 ÷ 4 = 17931) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 4) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (71724 ÷ 6 = 11954) | 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 | No (remainder 4) | 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 4) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | Yes (71724 ÷ 12 = 5977) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 71724 a prime number?
No. 71724 = × 3 × 43 × 139, so it is divisible by 2.
What are the factors of 71724?
1, 2, 3, 4, 6, 12, 43, 86, 129, 139, 172, 258, 278, 417, 516, 556, 834, 1668, 5977, 11954, 17931, 23908, 35862, 71724.
What is 71724 in binary?
10001100000101100 (hexadecimal 1182C, octal 214054).
What is the square root of 71724?
About 267.8134, exactly 2√17931.
Is 71724 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 71724?
It is a composite number with 24 divisors.