The number 71990
71990 is a composite number with 16 divisors. Its prime factorisation is 2 × 5 × 23 × 313. Divisors (16): 1, 2, 5, 10, 23, 46, 115, 230, 313, 626, 1565, 3130, 7199, 14398, 35995, 71990.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
71990 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
71990 is composite. Its prime factorisation is
- 3
The divisors add up to 135648; without 71990 itself that is 63658, so 71990 is deficient (63658 is less than 71990). Euler's totient φ(71990) = 27456 numbers up to 71990 share no factor with it.
- 4
The digits of 71990 add up to 26, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 94 steps to reach 1.
LaTeX source of the formulas on this page
\[ 71990 = 2 \times 5 \times 23 \times 313 \]
71990 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 135648 |
| Euler totient φ(n) | 27456 |
| Square | 5182560100 |
| Cube | 373092501599000 |
| Square root | 268.309523 |
| Digit sum / digital root | 26 / 8 |
| Collatz steps to 1 | 94 |
| Scientific notation | 7.199 × |
71990 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand nine hundred and ninety |
| Binary (base 2) | 10001100100110110 |
| Octal (base 8) | 214466 |
| Hexadecimal (base 16) | 11936 |
| Base 3 | 10122202022 |
| As time | 71990 seconds = 19 h 59 min 50 s |
Is 71990 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (71990 ÷ 2 = 35995) | 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 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (71990 ÷ 5 = 14398) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 2) | 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 6) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 8) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (71990 ÷ 10 = 7199) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 6) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 71990 a prime number?
No. 71990 = 2 × 5 × 23 × 313, so it is divisible by 2.
What are the factors of 71990?
1, 2, 5, 10, 23, 46, 115, 230, 313, 626, 1565, 3130, 7199, 14398, 35995, 71990.
What is 71990 in binary?
10001100100110110 (hexadecimal 11936, octal 214466).
What is the square root of 71990?
About 268.3095.
Is 71990 divisible by 3?
No. Its digits add up to 26, which is not a multiple of 3.
What is special about the number 71990?
It is a composite number with 16 divisors.