The number 71221
71221 is a composite number with 4 divisors. Its prime factorisation is 67 × 1063. Divisors (4): 1, 67, 1063, 71221.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 71221: a semiprime: 67 × 1063, the product of two primes.
- 2
71221 is composite. Its prime factorisation is
- 3
The divisors add up to 72352; without 71221 itself that is 1131, so 71221 is deficient (1131 is less than 71221). Euler's totient φ(71221) = 70092 numbers up to 71221 share no factor with it.
- 4
The digits of 71221 add up to 13, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 143 steps to reach 1.
LaTeX source of the formulas on this page
\[ 71221 = 67 \times 1063 \]
71221 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 72352 |
| Euler totient φ(n) | 70092 |
| Square | 5072430841 |
| Cube | 361263596926861 |
| Square root | 266.872629 |
| Digit sum / digital root | 13 / 4 |
| Collatz steps to 1 | 143 |
| Scientific notation | 7.1221 × |
71221 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand two hundred and twenty-one |
| Binary (base 2) | 10001011000110101 |
| Octal (base 8) | 213065 |
| Hexadecimal (base 16) | 11635 |
| Base 3 | 10121200211 |
| As time | 71221 seconds = 19 h 47 min 1 s |
Is 71221 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 1) | 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 1) | 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 4) | 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 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 71221 a prime number?
No. 71221 = 67 × 1063, so it is divisible by 67.
What are the factors of 71221?
1, 67, 1063, 71221.
What is 71221 in binary?
10001011000110101 (hexadecimal 11635, octal 213065).
What is the square root of 71221?
About 266.8726.
Is 71221 divisible by 3?
No. Its digits add up to 13, which is not a multiple of 3.
What is special about the number 71221?
71221 is a semiprime: 67 × 1063, the product of two primes.