The number 11021
11021 is a composite number with 4 divisors. Its prime factorisation is 103 × 107. Divisors (4): 1, 103, 107, 11021.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 11021: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 103 × 107, the product of two primes.
- 2
11021 is composite. Its prime factorisation is
- 3
The divisors add up to 11232; without 11021 itself that is 211, so 11021 is deficient (211 is less than 11021). Euler's totient φ(11021) = 10812 numbers up to 11021 share no factor with it.
- 4
The digits of 11021 add up to 5, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 161 steps to reach 1.
LaTeX source of the formulas on this page
\[ 11021 = 103 \times 107 \]
11021 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 11232 |
| Euler totient φ(n) | 10812 |
| Square | 121462441 |
| Cube | 1338637562261 |
| Square root | 104.980951 |
| Digit sum / digital root | 5 / 5 |
| Collatz steps to 1 | 161 |
| Scientific notation | 1.1021 × |
11021 in other forms
| Form | Value |
|---|---|
| In words | eleven thousand and twenty-one |
| Binary (base 2) | 10101100001101 |
| Octal (base 8) | 25415 |
| Hexadecimal (base 16) | 2B0D |
| Base 3 | 120010012 |
| As time | 11021 seconds = 3 h 3 min 41 s |
Is 11021 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 1) | 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 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 5) | 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 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 11021 a prime number?
No. 11021 = 103 × 107, so it is divisible by 103.
What are the factors of 11021?
1, 103, 107, 11021.
What is 11021 in binary?
10101100001101 (hexadecimal 2B0D, octal 25415).
What is the square root of 11021?
About 104.9810.
Is 11021 divisible by 3?
No. Its digits add up to 5, which is not a multiple of 3.
What is special about the number 11021?
11021 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 103 × 107, the product of two primes.