The number 31430
31430 is a composite number with 16 divisors. Its prime factorisation is 2 × 5 × 7 × 449. Divisors (16): 1, 2, 5, 7, 10, 14, 35, 70, 449, 898, 2245, 3143, 4490, 6286, 15715, 31430.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
31430 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
31430 is composite. Its prime factorisation is
- 3
The divisors add up to 64800; without 31430 itself that is 33370, so 31430 is abundant (33370 is more than 31430). Euler's totient φ(31430) = 10752 numbers up to 31430 share no factor with it.
- 4
The digits of 31430 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 103 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31430 = 2 \times 5 \times 7 \times 449 \]
31430 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 64800 |
| Euler totient φ(n) | 10752 |
| Square | 987844900 |
| Cube | 31047965207000 |
| Square root | 177.285081 |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 103 |
| Scientific notation | 3.143 × |
31430 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand four hundred and thirty |
| Binary (base 2) | 111101011000110 |
| Octal (base 8) | 75306 |
| Hexadecimal (base 16) | 7AC6 |
| Base 3 | 1121010002 |
| As time | 31430 seconds = 8 h 43 min 50 s |
Is 31430 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (31430 ÷ 2 = 15715) | 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 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (31430 ÷ 5 = 6286) | 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 | Yes (31430 ÷ 7 = 4490) | 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 6) | 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 | Yes (31430 ÷ 10 = 3143) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31430 a prime number?
No. 31430 = 2 × 5 × 7 × 449, so it is divisible by 2.
What are the factors of 31430?
1, 2, 5, 7, 10, 14, 35, 70, 449, 898, 2245, 3143, 4490, 6286, 15715, 31430.
What is 31430 in binary?
111101011000110 (hexadecimal 7AC6, octal 75306).
What is the square root of 31430?
About 177.2851.
Is 31430 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 31430?
It is a composite number with 16 divisors.