The number 71021
71021 is a composite number with 8 divisors. Its prime factorisation is 29 × 31 × 79. Divisors (8): 1, 29, 31, 79, 899, 2291, 2449, 71021.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
71021 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
71021 is composite. Its prime factorisation is
- 3
The divisors add up to 76800; without 71021 itself that is 5779, so 71021 is deficient (5779 is less than 71021). Euler's totient φ(71021) = 65520 numbers up to 71021 share no factor with it.
- 4
The digits of 71021 add up to 11, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 174 steps to reach 1.
LaTeX source of the formulas on this page
\[ 71021 = 29 \times 31 \times 79 \]
71021 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 76800 |
| Euler totient φ(n) | 65520 |
| Square | 5043982441 |
| Cube | 358228676942261 |
| Square root | 266.497655 |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 174 |
| Scientific notation | 7.1021 × |
71021 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand and twenty-one |
| Binary (base 2) | 10001010101101101 |
| Octal (base 8) | 212555 |
| Hexadecimal (base 16) | 1156D |
| Base 3 | 10121102102 |
| As time | 71021 seconds = 19 h 43 min 41 s |
Is 71021 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 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 5) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 6) | 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 2) | 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 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 71021 a prime number?
No. 71021 = 29 × 31 × 79, so it is divisible by 29.
What are the factors of 71021?
1, 29, 31, 79, 899, 2291, 2449, 71021.
What is 71021 in binary?
10001010101101101 (hexadecimal 1156D, octal 212555).
What is the square root of 71021?
About 266.4977.
Is 71021 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 71021?
It is a composite number with 8 divisors.