The number 71989
71989 is a composite number with 4 divisors. Its prime factorisation is 193 × 373. Divisors (4): 1, 193, 373, 71989.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 71989: a semiprime: 193 × 373, the product of two primes.
- 2
71989 is composite. Its prime factorisation is
- 3
The divisors add up to 72556; without 71989 itself that is 567, so 71989 is deficient (567 is less than 71989). Euler's totient φ(71989) = 71424 numbers up to 71989 share no factor with it.
- 4
The digits of 71989 add up to 34, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 50 steps to reach 1.
LaTeX source of the formulas on this page
\[ 71989 = 193 \times 373 \]
71989 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 72556 |
| Euler totient φ(n) | 71424 |
| Square | 5182416121 |
| Cube | 373076954134669 |
| Square root | 268.307659 |
| Digit sum / digital root | 34 / 7 |
| Collatz steps to 1 | 50 |
| Scientific notation | 7.1989 × |
71989 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand nine hundred and eighty-nine |
| Binary (base 2) | 10001100100110101 |
| Octal (base 8) | 214465 |
| Hexadecimal (base 16) | 11935 |
| Base 3 | 10122202021 |
| As time | 71989 seconds = 19 h 59 min 49 s |
Is 71989 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 4) | 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 1) | 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 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 9) | 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 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 71989 a prime number?
No. 71989 = 193 × 373, so it is divisible by 193.
What are the factors of 71989?
1, 193, 373, 71989.
What is 71989 in binary?
10001100100110101 (hexadecimal 11935, octal 214465).
What is the square root of 71989?
About 268.3077.
Is 71989 divisible by 3?
No. Its digits add up to 34, which is not a multiple of 3.
What is special about the number 71989?
71989 is a semiprime: 193 × 373, the product of two primes.