The number 31438
31438 is a composite number with 8 divisors. Its prime factorisation is 2 × 11 × 1429. Divisors (8): 1, 2, 11, 22, 1429, 2858, 15719, 31438.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
31438 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
31438 is composite. Its prime factorisation is
- 3
The divisors add up to 51480; without 31438 itself that is 20042, so 31438 is deficient (20042 is less than 31438). Euler's totient φ(31438) = 14280 numbers up to 31438 share no factor with it.
- 4
The digits of 31438 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 129 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31438 = 2 \times 11 \times 1429 \]
31438 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 51480 |
| Euler totient φ(n) | 14280 |
| Square | 988347844 |
| Cube | 31071679519672 |
| Square root | 177.307642 |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 129 |
| Scientific notation | 3.1438 × |
31438 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand four hundred and thirty-eight |
| Binary (base 2) | 111101011001110 |
| Octal (base 8) | 75316 |
| Hexadecimal (base 16) | 7ACE |
| Base 3 | 1121010101 |
| As time | 31438 seconds = 8 h 43 min 58 s |
Is 31438 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (31438 ÷ 2 = 15719) | 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 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 1) | 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 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 8) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (31438 ÷ 11 = 2858) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 10) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31438 a prime number?
No. 31438 = 2 × 11 × 1429, so it is divisible by 2.
What are the factors of 31438?
1, 2, 11, 22, 1429, 2858, 15719, 31438.
What is 31438 in binary?
111101011001110 (hexadecimal 7ACE, octal 75316).
What is the square root of 31438?
About 177.3076.
Is 31438 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 31438?
It is a composite number with 8 divisors.