The number 12440
12440 is a composite number with 16 divisors. Its prime factorisation is × 5 × 311. Divisors (16): 1, 2, 4, 5, 8, 10, 20, 40, 311, 622, 1244, 1555, 2488, 3110, 6220, 12440.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
12440 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
12440 is composite. Its prime factorisation is
- 3
The divisors add up to 28080; without 12440 itself that is 15640, so 12440 is abundant (15640 is more than 12440). Euler's totient φ(12440) = 4960 numbers up to 12440 share no factor with it.
- 4
The digits of 12440 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 37 steps to reach 1.
LaTeX source of the formulas on this page
\[ 12440 = 2^{3} \times 5 \times 311 \]12440 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 28080 |
| Euler totient φ(n) | 4960 |
| Square | 154753600 |
| Cube | 1925134784000 |
| Square root | 111.534748 (= 2√3110) |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 37 |
| Scientific notation | 1.244 × |
12440 in other forms
| Form | Value |
|---|---|
| In words | twelve thousand four hundred and forty |
| Binary (base 2) | 11000010011000 |
| Octal (base 8) | 30230 |
| Hexadecimal (base 16) | 3098 |
| Base 3 | 122001202 |
| As time | 12440 seconds = 3 h 27 min 20 s |
Is 12440 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (12440 ÷ 2 = 6220) | 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 (12440 ÷ 4 = 3110) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (12440 ÷ 5 = 2488) | 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 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 | Yes (12440 ÷ 8 = 1555) | 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 (12440 ÷ 10 = 1244) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 10) | 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 12440 a prime number?
No. 12440 = × 5 × 311, so it is divisible by 2.
What are the factors of 12440?
1, 2, 4, 5, 8, 10, 20, 40, 311, 622, 1244, 1555, 2488, 3110, 6220, 12440.
What is 12440 in binary?
11000010011000 (hexadecimal 3098, octal 30230).
What is the square root of 12440?
About 111.5347, exactly 2√3110.
Is 12440 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 12440?
It is a composite number with 16 divisors.