The number 41821
41821 is a composite number with 4 divisors. Its prime factorisation is 13 × 3217. Divisors (4): 1, 13, 3217, 41821.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 41821: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 13 × 3217, the product of two primes.
- 2
41821 is composite. Its prime factorisation is
- 3
The divisors add up to 45052; without 41821 itself that is 3231, so 41821 is deficient (3231 is less than 41821). Euler's totient φ(41821) = 38592 numbers up to 41821 share no factor with it.
- 4
The digits of 41821 add up to 16, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 57 steps to reach 1.
LaTeX source of the formulas on this page
\[ 41821 = 13 \times 3217 \]
41821 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 45052 |
| Euler totient φ(n) | 38592 |
| Square | 1748996041 |
| Cube | 73144763430661 |
| Square root | 204.501834 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 57 |
| Scientific notation | 4.1821 × |
41821 in other forms
| Form | Value |
|---|---|
| In words | forty-one thousand eight hundred and twenty-one |
| Binary (base 2) | 1010001101011101 |
| Octal (base 8) | 121535 |
| Hexadecimal (base 16) | A35D |
| Base 3 | 2010100221 |
| As time | 41821 seconds = 11 h 37 min 1 s |
Is 41821 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 3) | 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 7) | 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 10) | 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 41821 a prime number?
No. 41821 = 13 × 3217, so it is divisible by 13.
What are the factors of 41821?
1, 13, 3217, 41821.
What is 41821 in binary?
1010001101011101 (hexadecimal A35D, octal 121535).
What is the square root of 41821?
About 204.5018.
Is 41821 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 41821?
41821 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 13 × 3217, the product of two primes.