The number 3728
3728 is a composite number with 10 divisors. Its prime factorisation is × 233. Divisors (10): 1, 2, 4, 8, 16, 233, 466, 932, 1864, 3728.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
3728 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
3728 is composite. Its prime factorisation is
- 3
The divisors add up to 7254; without 3728 itself that is 3526, so 3728 is deficient (3526 is less than 3728). Euler's totient φ(3728) = 1856 numbers up to 3728 share no factor with it.
- 4
The digits of 3728 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 87 steps to reach 1.
LaTeX source of the formulas on this page
\[ 3728 = 2^{4} \times 233 \]3728 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 10 |
| Sum of divisors | 7254 |
| Euler totient φ(n) | 1856 |
| Square | 13897984 |
| Cube | 51811684352 |
| Square root | 61.057350 (= 4√233) |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 87 |
| Scientific notation | 3.728 × |
3728 in other forms
| Form | Value |
|---|---|
| In words | three thousand seven hundred and twenty-eight |
| Roman numerals | MMMDCCXXVIII |
| Binary (base 2) | 111010010000 |
| Octal (base 8) | 7220 |
| Hexadecimal (base 16) | E90 |
| Base 3 | 12010002 |
| As time | 3728 seconds = 1 h 2 min 8 s |
Is 3728 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (3728 ÷ 2 = 1864) | 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 (3728 ÷ 4 = 932) | 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 4) | 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 (3728 ÷ 8 = 466) | 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 | No (remainder 8) | 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 3728 a prime number?
No. 3728 = × 233, so it is divisible by 2.
What are the factors of 3728?
1, 2, 4, 8, 16, 233, 466, 932, 1864, 3728.
What is 3728 in binary?
111010010000 (hexadecimal E90, octal 7220).
What is the square root of 3728?
About 61.0574, exactly 4√233.
What is 3728 in Roman numerals?
MMMDCCXXVIII.
Is 3728 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 3728?
It is a composite number with 10 divisors.