The number 11388
11388 is a composite number with 24 divisors. Its prime factorisation is × 3 × 13 × 73. Divisors (24): 1, 2, 3, 4, 6, 12, 13, 26, 39, 52, 73, 78, 146, 156, 219, 292 … 11388.
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How to work it out
- 1
What is special about 11388: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
11388 is composite. Its prime factorisation is
- 3
The divisors add up to 29008; without 11388 itself that is 17620, so 11388 is abundant (17620 is more than 11388). Euler's totient φ(11388) = 3456 numbers up to 11388 share no factor with it.
- 4
The digits of 11388 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 174 steps to reach 1.
LaTeX source of the formulas on this page
\[ 11388 = 2^{2} \times 3 \times 13 \times 73 \]11388 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 29008 |
| Euler totient φ(n) | 3456 |
| Square | 129686544 |
| Cube | 1476870363072 |
| Square root | 106.714573 (= 2√2847) |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 174 |
| Scientific notation | 1.1388 × |
11388 in other forms
| Form | Value |
|---|---|
| In words | eleven thousand three hundred and eighty-eight |
| Binary (base 2) | 10110001111100 |
| Octal (base 8) | 26174 |
| Hexadecimal (base 16) | 2C7C |
| Base 3 | 120121210 |
| As time | 11388 seconds = 3 h 9 min 48 s |
Is 11388 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (11388 ÷ 2 = 5694) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (11388 ÷ 3 = 3796) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (11388 ÷ 4 = 2847) | 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 | Yes (11388 ÷ 6 = 1898) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 6) | 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 4) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | 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 | No (remainder 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | Yes (11388 ÷ 12 = 949) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 11388 a prime number?
No. 11388 = × 3 × 13 × 73, so it is divisible by 2.
What are the factors of 11388?
1, 2, 3, 4, 6, 12, 13, 26, 39, 52, 73, 78, 146, 156, 219, 292, 438, 876, 949, 1898, 2847, 3796, 5694, 11388.
What is 11388 in binary?
10110001111100 (hexadecimal 2C7C, octal 26174).
What is the square root of 11388?
About 106.7146, exactly 2√2847.
Is 11388 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 11388?
11388 is a happy number: repeatedly adding the squares of its digits reaches 1.