The number 1604
1604 is a composite number with 6 divisors. Its prime factorisation is × 401. Divisors (6): 1, 2, 4, 401, 802, 1604.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
1604 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
1604 is composite. Its prime factorisation is
- 3
The divisors add up to 2814; without 1604 itself that is 1210, so 1604 is deficient (1210 is less than 1604). Euler's totient φ(1604) = 800 numbers up to 1604 share no factor with it.
- 4
The digits of 1604 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 21 steps to reach 1.
LaTeX source of the formulas on this page
\[ 1604 = 2^{2} \times 401 \]1604 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 2814 |
| Euler totient φ(n) | 800 |
| Square | 2572816 |
| Cube | 4126796864 |
| Square root | 40.049969 (= 2√401) |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 21 |
| Scientific notation | 1.604 × |
1604 in other forms
| Form | Value |
|---|---|
| In words | one thousand six hundred and four |
| Roman numerals | MDCIV |
| Binary (base 2) | 11001000100 |
| Octal (base 8) | 3104 |
| Hexadecimal (base 16) | 644 |
| Base 3 | 2012102 |
| As time | 1604 seconds = 26 min 44 s |
Is 1604 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (1604 ÷ 2 = 802) | 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 (1604 ÷ 4 = 401) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 4) | 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 | No (remainder 4) | 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 4) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | 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 1604 a prime number?
No. 1604 = × 401, so it is divisible by 2.
What are the factors of 1604?
1, 2, 4, 401, 802, 1604.
What is 1604 in binary?
11001000100 (hexadecimal 644, octal 3104).
What is the square root of 1604?
About 40.0500, exactly 2√401.
What is 1604 in Roman numerals?
MDCIV.
Is 1604 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 1604?
It is a composite number with 6 divisors.