The number 71421
71421 is a composite number with 16 divisors. Its prime factorisation is 3 × 7 × 19 × 179. Divisors (16): 1, 3, 7, 19, 21, 57, 133, 179, 399, 537, 1253, 3401, 3759, 10203, 23807, 71421.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
71421 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
71421 is composite. Its prime factorisation is
- 3
The divisors add up to 115200; without 71421 itself that is 43779, so 71421 is deficient (43779 is less than 71421). Euler's totient φ(71421) = 38448 numbers up to 71421 share no factor with it.
- 4
The digits of 71421 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 125 steps to reach 1.
LaTeX source of the formulas on this page
\[ 71421 = 3 \times 7 \times 19 \times 179 \]
71421 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 115200 |
| Euler totient φ(n) | 38448 |
| Square | 5100959241 |
| Cube | 364315609951461 |
| Square root | 267.247077 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 125 |
| Scientific notation | 7.1421 × |
71421 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand four hundred and twenty-one |
| Binary (base 2) | 10001011011111101 |
| Octal (base 8) | 213375 |
| Hexadecimal (base 16) | 116FD |
| Base 3 | 10121222020 |
| As time | 71421 seconds = 19 h 50 min 21 s |
Is 71421 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 (71421 ÷ 3 = 23807) | 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 | Yes (71421 ÷ 7 = 10203) | 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | 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 9) | 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 71421 a prime number?
No. 71421 = 3 × 7 × 19 × 179, so it is divisible by 3.
What are the factors of 71421?
1, 3, 7, 19, 21, 57, 133, 179, 399, 537, 1253, 3401, 3759, 10203, 23807, 71421.
What is 71421 in binary?
10001011011111101 (hexadecimal 116FD, octal 213375).
What is the square root of 71421?
About 267.2471.
Is 71421 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 71421?
It is a composite number with 16 divisors.