The number 31124
31124 is a composite number with 12 divisors. Its prime factorisation is × 31 × 251. Divisors (12): 1, 2, 4, 31, 62, 124, 251, 502, 1004, 7781, 15562, 31124.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 31124: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
31124 is composite. Its prime factorisation is
- 3
The divisors add up to 56448; without 31124 itself that is 25324, so 31124 is deficient (25324 is less than 31124). Euler's totient φ(31124) = 15000 numbers up to 31124 share no factor with it.
- 4
The digits of 31124 add up to 11, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 41 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31124 = 2^{2} \times 31 \times 251 \]31124 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 56448 |
| Euler totient φ(n) | 15000 |
| Square | 968703376 |
| Cube | 30149923874624 |
| Square root | 176.419954 (= 2√7781) |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 41 |
| Scientific notation | 3.1124 × |
31124 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand one hundred and twenty-four |
| Binary (base 2) | 111100110010100 |
| Octal (base 8) | 74624 |
| Hexadecimal (base 16) | 7994 |
| Base 3 | 1120200202 |
| As time | 31124 seconds = 8 h 38 min 44 s |
Is 31124 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (31124 ÷ 2 = 15562) | 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 | Yes (31124 ÷ 4 = 7781) | 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 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 4) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 4) | 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 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31124 a prime number?
No. 31124 = × 31 × 251, so it is divisible by 2.
What are the factors of 31124?
1, 2, 4, 31, 62, 124, 251, 502, 1004, 7781, 15562, 31124.
What is 31124 in binary?
111100110010100 (hexadecimal 7994, octal 74624).
What is the square root of 31124?
About 176.4200, exactly 2√7781.
Is 31124 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 31124?
31124 is a happy number: repeatedly adding the squares of its digits reaches 1.