The number 74205
74205 is a composite number with 24 divisors. Its prime factorisation is × 5 × 17 × 97. Divisors (24): 1, 3, 5, 9, 15, 17, 45, 51, 85, 97, 153, 255, 291, 485, 765, 873 … 74205.
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How to work it out
- 1
What is special about 74205: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
74205 is composite. Its prime factorisation is
- 3
The divisors add up to 137592; without 74205 itself that is 63387, so 74205 is deficient (63387 is less than 74205). Euler's totient φ(74205) = 36864 numbers up to 74205 share no factor with it.
- 4
The digits of 74205 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 156 steps to reach 1.
LaTeX source of the formulas on this page
\[ 74205 = 3^{2} \times 5 \times 17 \times 97 \]74205 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 137592 |
| Euler totient φ(n) | 36864 |
| Square | 5506382025 |
| Cube | 408601078165125 |
| Square root | 272.405947 (= 3√8245) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 156 |
| Scientific notation | 7.4205 × |
74205 in other forms
| Form | Value |
|---|---|
| In words | seventy-four thousand two hundred and five |
| Binary (base 2) | 10010000111011101 |
| Octal (base 8) | 220735 |
| Hexadecimal (base 16) | 121DD |
| Base 3 | 10202210100 |
| As time | 74205 seconds = 20 h 36 min 45 s |
Is 74205 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 (74205 ÷ 3 = 24735) | 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 | Yes (74205 ÷ 5 = 14841) | 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 5) | 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 | Yes (74205 ÷ 9 = 8245) | 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 10) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 74205 a prime number?
No. 74205 = × 5 × 17 × 97, so it is divisible by 3.
What are the factors of 74205?
1, 3, 5, 9, 15, 17, 45, 51, 85, 97, 153, 255, 291, 485, 765, 873, 1455, 1649, 4365, 4947, 8245, 14841, 24735, 74205.
What is 74205 in binary?
10010000111011101 (hexadecimal 121DD, octal 220735).
What is the square root of 74205?
About 272.4059, exactly 3√8245.
Is 74205 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 74205?
74205 is a happy number: repeatedly adding the squares of its digits reaches 1.