The number 31021
31021 is a composite number with 4 divisors. Its prime factorisation is 67 × 463. Divisors (4): 1, 67, 463, 31021.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 31021: a semiprime: 67 × 463, the product of two primes.
- 2
31021 is composite. Its prime factorisation is
- 3
The divisors add up to 31552; without 31021 itself that is 531, so 31021 is deficient (531 is less than 31021). Euler's totient φ(31021) = 30492 numbers up to 31021 share no factor with it.
- 4
The digits of 31021 add up to 7, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 54 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31021 = 67 \times 463 \]
31021 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 31552 |
| Euler totient φ(n) | 30492 |
| Square | 962302441 |
| Cube | 29851584022261 |
| Square root | 176.127795 |
| Digit sum / digital root | 7 / 7 |
| Collatz steps to 1 | 54 |
| Scientific notation | 3.1021 × |
31021 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand and twenty-one |
| Binary (base 2) | 111100100101101 |
| Octal (base 8) | 74455 |
| Hexadecimal (base 16) | 792D |
| Base 3 | 1120112221 |
| As time | 31021 seconds = 8 h 37 min 1 s |
Is 31021 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 4) | 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 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 1) | 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 31021 a prime number?
No. 31021 = 67 × 463, so it is divisible by 67.
What are the factors of 31021?
1, 67, 463, 31021.
What is 31021 in binary?
111100100101101 (hexadecimal 792D, octal 74455).
What is the square root of 31021?
About 176.1278.
Is 31021 divisible by 3?
No. Its digits add up to 7, which is not a multiple of 3.
What is special about the number 31021?
31021 is a semiprime: 67 × 463, the product of two primes.