The number 31241
31241 is a composite number with 4 divisors. Its prime factorisation is 7 × 4463. Divisors (4): 1, 7, 4463, 31241.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 31241: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 7 × 4463, the product of two primes.
- 2
31241 is composite. Its prime factorisation is
- 3
The divisors add up to 35712; without 31241 itself that is 4471, so 31241 is deficient (4471 is less than 31241). Euler's totient φ(31241) = 26772 numbers up to 31241 share no factor with it.
- 4
The digits of 31241 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 147 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31241 = 7 \times 4463 \]
31241 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 35712 |
| Euler totient φ(n) | 26772 |
| Square | 976000081 |
| Cube | 30491218530521 |
| Square root | 176.751238 |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 147 |
| Scientific notation | 3.1241 × |
31241 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand two hundred and forty-one |
| Binary (base 2) | 111101000001001 |
| Octal (base 8) | 75011 |
| Hexadecimal (base 16) | 7A09 |
| Base 3 | 1120212002 |
| As time | 31241 seconds = 8 h 40 min 41 s |
Is 31241 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 2) | 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 5) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (31241 ÷ 7 = 4463) | 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 1) | 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 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 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31241 a prime number?
No. 31241 = 7 × 4463, so it is divisible by 7.
What are the factors of 31241?
1, 7, 4463, 31241.
What is 31241 in binary?
111101000001001 (hexadecimal 7A09, octal 75011).
What is the square root of 31241?
About 176.7512.
Is 31241 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 31241?
31241 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 7 × 4463, the product of two primes.