The number 16409
16409 is a composite number with 4 divisors. Its prime factorisation is 61 × 269. Divisors (4): 1, 61, 269, 16409.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 16409: a semiprime: 61 × 269, the product of two primes.
- 2
16409 is composite. Its prime factorisation is
- 3
The divisors add up to 16740; without 16409 itself that is 331, so 16409 is deficient (331 is less than 16409). Euler's totient φ(16409) = 16080 numbers up to 16409 share no factor with it.
- 4
The digits of 16409 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 97 steps to reach 1.
LaTeX source of the formulas on this page
\[ 16409 = 61 \times 269 \]
16409 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 16740 |
| Euler totient φ(n) | 16080 |
| Square | 269255281 |
| Cube | 4418209905929 |
| Square root | 128.097619 |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 97 |
| Scientific notation | 1.6409 × |
16409 in other forms
| Form | Value |
|---|---|
| In words | sixteen thousand four hundred and nine |
| Binary (base 2) | 100000000011001 |
| Octal (base 8) | 40031 |
| Hexadecimal (base 16) | 4019 |
| Base 3 | 211111202 |
| As time | 16409 seconds = 4 h 33 min 29 s |
Is 16409 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | 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 | No (remainder 1) | 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 5) | 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 1) | 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 9) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 8) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 16409 a prime number?
No. 16409 = 61 × 269, so it is divisible by 61.
What are the factors of 16409?
1, 61, 269, 16409.
What is 16409 in binary?
100000000011001 (hexadecimal 4019, octal 40031).
What is the square root of 16409?
About 128.0976.
Is 16409 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 16409?
16409 is a semiprime: 61 × 269, the product of two primes.