The number 21349
21349 is a binary palindrome (101001101100101). Its prime factorisation is 37 × 577. Divisors (4): 1, 37, 577, 21349.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 21349: a binary palindrome (101001101100101); a semiprime: 37 × 577, the product of two primes.
- 2
21349 is composite. Its prime factorisation is
- 3
The divisors add up to 21964; without 21349 itself that is 615, so 21349 is deficient (615 is less than 21349). Euler's totient φ(21349) = 20736 numbers up to 21349 share no factor with it.
- 4
The digits of 21349 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 56 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21349 = 37 \times 577 \]
21349 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 21964 |
| Euler totient φ(n) | 20736 |
| Square | 455779801 |
| Cube | 9730442971549 |
| Square root | 146.112970 |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 56 |
| Scientific notation | 2.1349 × |
21349 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand three hundred and forty-nine |
| Binary (base 2) | 101001101100101 |
| Octal (base 8) | 51545 |
| Hexadecimal (base 16) | 5365 |
| Base 3 | 1002021201 |
| As time | 21349 seconds = 5 h 55 min 49 s |
Is 21349 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 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 1) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 6) | 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 5) | 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 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 21349 a prime number?
No. 21349 = 37 × 577, so it is divisible by 37.
What are the factors of 21349?
1, 37, 577, 21349.
What is 21349 in binary?
101001101100101 (hexadecimal 5365, octal 51545).
What is the square root of 21349?
About 146.1130.
Is 21349 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 21349?
21349 is a binary palindrome (101001101100101); a semiprime: 37 × 577, the product of two primes.