The number 37981
37981 is a composite number with 4 divisors. Its prime factorisation is 19 × 1999. Divisors (4): 1, 19, 1999, 37981.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 37981: a semiprime: 19 × 1999, the product of two primes.
- 2
37981 is composite. Its prime factorisation is
- 3
The divisors add up to 40000; without 37981 itself that is 2019, so 37981 is deficient (2019 is less than 37981). Euler's totient φ(37981) = 35964 numbers up to 37981 share no factor with it.
- 4
The digits of 37981 add up to 28, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 155 steps to reach 1.
LaTeX source of the formulas on this page
\[ 37981 = 19 \times 1999 \]
37981 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 40000 |
| Euler totient φ(n) | 35964 |
| Square | 1442556361 |
| Cube | 54789733147141 |
| Square root | 194.887147 |
| Digit sum / digital root | 28 / 1 |
| Collatz steps to 1 | 155 |
| Scientific notation | 3.7981 × |
37981 in other forms
| Form | Value |
|---|---|
| In words | thirty-seven thousand nine hundred and eighty-one |
| Binary (base 2) | 1001010001011101 |
| Octal (base 8) | 112135 |
| Hexadecimal (base 16) | 945D |
| Base 3 | 1221002201 |
| As time | 37981 seconds = 10 h 33 min 1 s |
Is 37981 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 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 1) | 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 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 37981 a prime number?
No. 37981 = 19 × 1999, so it is divisible by 19.
What are the factors of 37981?
1, 19, 1999, 37981.
What is 37981 in binary?
1001010001011101 (hexadecimal 945D, octal 112135).
What is the square root of 37981?
About 194.8871.
Is 37981 divisible by 3?
No. Its digits add up to 28, which is not a multiple of 3.
What is special about the number 37981?
37981 is a semiprime: 19 × 1999, the product of two primes.