The number 31425
31425 is a composite number with 12 divisors. Its prime factorisation is 3 × × 419. Divisors (12): 1, 3, 5, 15, 25, 75, 419, 1257, 2095, 6285, 10475, 31425.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 31425: a Harshad number: divisible by its digit sum 15.
- 2
31425 is composite. Its prime factorisation is
- 3
The divisors add up to 52080; without 31425 itself that is 20655, so 31425 is deficient (20655 is less than 31425). Euler's totient φ(31425) = 16720 numbers up to 31425 share no factor with it.
- 4
The digits of 31425 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 85 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31425 = 3 \times 5^{2} \times 419 \]31425 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 52080 |
| Euler totient φ(n) | 16720 |
| Square | 987530625 |
| Cube | 31033149890625 |
| Square root | 177.270979 (= 5√1257) |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 85 |
| Scientific notation | 3.1425 × |
31425 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand four hundred and twenty-five |
| Binary (base 2) | 111101011000001 |
| Octal (base 8) | 75301 |
| Hexadecimal (base 16) | 7AC1 |
| Base 3 | 1121002220 |
| As time | 31425 seconds = 8 h 43 min 45 s |
Is 31425 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 | Yes (31425 ÷ 3 = 10475) | 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 | Yes (31425 ÷ 5 = 6285) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 3) | 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 1) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 5) | 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 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31425 a prime number?
No. 31425 = 3 × × 419, so it is divisible by 3.
What are the factors of 31425?
1, 3, 5, 15, 25, 75, 419, 1257, 2095, 6285, 10475, 31425.
What is 31425 in binary?
111101011000001 (hexadecimal 7AC1, octal 75301).
What is the square root of 31425?
About 177.2710, exactly 5√1257.
Is 31425 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 31425?
31425 is a Harshad number: divisible by its digit sum 15.