The number 188
188 is a composite number with 6 divisors. Its prime factorisation is × 47. Divisors (6): 1, 2, 4, 47, 94, 188.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 188: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
188 is composite. Its prime factorisation is
- 3
The divisors add up to 336; without 188 itself that is 148, so 188 is deficient (148 is less than 188). Euler's totient φ(188) = 92 numbers up to 188 share no factor with it.
- 4
The digits of 188 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 106 steps to reach 1.
LaTeX source of the formulas on this page
\[ 188 = 2^{2} \times 47 \]188 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 336 |
| Euler totient φ(n) | 92 |
| Square | 35344 |
| Cube | 6644672 |
| Square root | 13.711309 (= 2√47) |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 106 |
| Scientific notation | 1.88 × |
188 in other forms
| Form | Value |
|---|---|
| In words | one hundred and eighty-eight |
| Roman numerals | CLXXXVIII |
| Binary (base 2) | 10111100 |
| Octal (base 8) | 274 |
| Hexadecimal (base 16) | BC |
| Base 3 | 20222 |
| As time | 188 seconds = 3 min 8 s |
Is 188 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (188 ÷ 2 = 94) | 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 (188 ÷ 4 = 47) | 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 2) | 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 8) | 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 1) | 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 188 a prime number?
No. 188 = × 47, so it is divisible by 2.
What are the factors of 188?
1, 2, 4, 47, 94, 188.
What is 188 in binary?
10111100 (hexadecimal BC, octal 274).
What is the square root of 188?
About 13.7113, exactly 2√47.
What is 188 in Roman numerals?
CLXXXVIII.
Is 188 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 188?
188 is a happy number: repeatedly adding the squares of its digits reaches 1.