The number 35821
35821 is a composite number with 4 divisors. Its prime factorisation is 113 × 317. Divisors (4): 1, 113, 317, 35821.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 35821: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 113 × 317, the product of two primes.
- 2
35821 is composite. Its prime factorisation is
- 3
The divisors add up to 36252; without 35821 itself that is 431, so 35821 is deficient (431 is less than 35821). Euler's totient φ(35821) = 35392 numbers up to 35821 share no factor with it.
- 4
The digits of 35821 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 98 steps to reach 1.
LaTeX source of the formulas on this page
\[ 35821 = 113 \times 317 \]
35821 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 36252 |
| Euler totient φ(n) | 35392 |
| Square | 1283144041 |
| Cube | 45963502692661 |
| Square root | 189.264365 |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 98 |
| Scientific notation | 3.5821 × |
35821 in other forms
| Form | Value |
|---|---|
| In words | thirty-five thousand eight hundred and twenty-one |
| Binary (base 2) | 1000101111101101 |
| Octal (base 8) | 105755 |
| Hexadecimal (base 16) | 8BED |
| Base 3 | 1211010201 |
| As time | 35821 seconds = 9 h 57 min 1 s |
Is 35821 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 1) | 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 2) | 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 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 5) | 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 35821 a prime number?
No. 35821 = 113 × 317, so it is divisible by 113.
What are the factors of 35821?
1, 113, 317, 35821.
What is 35821 in binary?
1000101111101101 (hexadecimal 8BED, octal 105755).
What is the square root of 35821?
About 189.2644.
Is 35821 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 35821?
35821 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 113 × 317, the product of two primes.