The number 16399
16399 is a composite number with 6 divisors. Its prime factorisation is Ć 31. Divisors (6): 1, 23, 31, 529, 713, 16399.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 16399: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
16399 is composite. Its prime factorisation is
- 3
The divisors add up to 17696; without 16399 itself that is 1297, so 16399 is deficient (1297 is less than 16399). Euler's totient Ļ(16399) = 15180 numbers up to 16399 share no factor with it.
- 4
The digits of 16399 add up to 28, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 115 steps to reach 1.
LaTeX source of the formulas on this page
\[ 16399 = 23^{2} \times 31 \]16399 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 17696 |
| Euler totient Ļ(n) | 15180 |
| Square | 268927201 |
| Cube | 4410137169199 |
| Square root | 128.058580 (= 23ā31) |
| Digit sum / digital root | 28 / 1 |
| Collatz steps to 1 | 115 |
| Scientific notation | 1.6399 Ć |
16399 in other forms
| Form | Value |
|---|---|
| In words | sixteen thousand three hundred and ninety-nine |
| Binary (base 2) | 100000000001111 |
| Octal (base 8) | 40017 |
| Hexadecimal (base 16) | 400F |
| Base 3 | 211111101 |
| As time | 16399 seconds = 4 h 33 min 19 s |
Is 16399 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 1) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | 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 1) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 5) | 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 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | 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 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 16399 a prime number?
No. 16399 = Ć 31, so it is divisible by 23.
What are the factors of 16399?
1, 23, 31, 529, 713, 16399.
What is 16399 in binary?
100000000001111 (hexadecimal 400F, octal 40017).
What is the square root of 16399?
About 128.0586, exactly 23ā31.
Is 16399 divisible by 3?
No. Its digits add up to 28, which is not a multiple of 3.
What is special about the number 16399?
16399 is a happy number: repeatedly adding the squares of its digits reaches 1.