The number 1628
1628 is a composite number with 12 divisors. Its prime factorisation is × 11 × 37. Divisors (12): 1, 2, 4, 11, 22, 37, 44, 74, 148, 407, 814, 1628.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
1628 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
1628 is composite. Its prime factorisation is
- 3
The divisors add up to 3192; without 1628 itself that is 1564, so 1628 is deficient (1564 is less than 1628). Euler's totient φ(1628) = 720 numbers up to 1628 share no factor with it.
- 4
The digits of 1628 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 42 steps to reach 1.
LaTeX source of the formulas on this page
\[ 1628 = 2^{2} \times 11 \times 37 \]1628 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 3192 |
| Euler totient φ(n) | 720 |
| Square | 2650384 |
| Cube | 4314825152 |
| Square root | 40.348482 (= 2√407) |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 42 |
| Scientific notation | 1.628 × |
1628 in other forms
| Form | Value |
|---|---|
| In words | one thousand six hundred and twenty-eight |
| Roman numerals | MDCXXVIII |
| Binary (base 2) | 11001011100 |
| Octal (base 8) | 3134 |
| Hexadecimal (base 16) | 65C |
| Base 3 | 2020022 |
| As time | 1628 seconds = 27 min 8 s |
Is 1628 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (1628 ÷ 2 = 814) | 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 (1628 ÷ 4 = 407) | 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 | 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 | Yes (1628 ÷ 11 = 148) | 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 1628 a prime number?
No. 1628 = × 11 × 37, so it is divisible by 2.
What are the factors of 1628?
1, 2, 4, 11, 22, 37, 44, 74, 148, 407, 814, 1628.
What is 1628 in binary?
11001011100 (hexadecimal 65C, octal 3134).
What is the square root of 1628?
About 40.3485, exactly 2√407.
What is 1628 in Roman numerals?
MDCXXVIII.
Is 1628 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 1628?
It is a composite number with 12 divisors.