The number 20355
20355 is a composite number with 16 divisors. Its prime factorisation is 3 × 5 × 23 × 59. Divisors (16): 1, 3, 5, 15, 23, 59, 69, 115, 177, 295, 345, 885, 1357, 4071, 6785, 20355.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 20355: a Harshad number: divisible by its digit sum 15.
- 2
20355 is composite. Its prime factorisation is
- 3
The divisors add up to 34560; without 20355 itself that is 14205, so 20355 is deficient (14205 is less than 20355). Euler's totient φ(20355) = 10208 numbers up to 20355 share no factor with it.
- 4
The digits of 20355 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 35 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20355 = 3 \times 5 \times 23 \times 59 \]
20355 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 34560 |
| Euler totient φ(n) | 10208 |
| Square | 414326025 |
| Cube | 8433606238875 |
| Square root | 142.670950 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 35 |
| Scientific notation | 2.0355 × |
20355 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand three hundred and fifty-five |
| Binary (base 2) | 100111110000011 |
| Octal (base 8) | 47603 |
| Hexadecimal (base 16) | 4F83 |
| Base 3 | 1000220220 |
| As time | 20355 seconds = 5 h 39 min 15 s |
Is 20355 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 | Yes (20355 ÷ 3 = 6785) | 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 | Yes (20355 ÷ 5 = 4071) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 3) | 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 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 5) | 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 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 20355 a prime number?
No. 20355 = 3 × 5 × 23 × 59, so it is divisible by 3.
What are the factors of 20355?
1, 3, 5, 15, 23, 59, 69, 115, 177, 295, 345, 885, 1357, 4071, 6785, 20355.
What is 20355 in binary?
100111110000011 (hexadecimal 4F83, octal 47603).
What is the square root of 20355?
About 142.6710.
Is 20355 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 20355?
20355 is a Harshad number: divisible by its digit sum 15.