The number 61005
61005 is a composite number with 24 divisors. Its prime factorisation is 3 × 5 × × 83. Divisors (24): 1, 3, 5, 7, 15, 21, 35, 49, 83, 105, 147, 245, 249, 415, 581, 735 … 61005.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
61005 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
61005 is composite. Its prime factorisation is
- 3
The divisors add up to 114912; without 61005 itself that is 53907, so 61005 is deficient (53907 is less than 61005). Euler's totient φ(61005) = 27552 numbers up to 61005 share no factor with it.
- 4
The digits of 61005 add up to 12, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 86 steps to reach 1.
LaTeX source of the formulas on this page
\[ 61005 = 3 \times 5 \times 7^{2} \times 83 \]61005 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 114912 |
| Euler totient φ(n) | 27552 |
| Square | 3721610025 |
| Cube | 227036819575125 |
| Square root | 246.991903 (= 7√1245) |
| Digit sum / digital root | 12 / 3 |
| Collatz steps to 1 | 86 |
| Scientific notation | 6.1005 × |
61005 in other forms
| Form | Value |
|---|---|
| In words | sixty-one thousand and five |
| Binary (base 2) | 1110111001001101 |
| Octal (base 8) | 167115 |
| Hexadecimal (base 16) | EE4D |
| Base 3 | 10002200110 |
| As time | 61005 seconds = 16 h 56 min 45 s |
Is 61005 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 (61005 ÷ 3 = 20335) | 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 (61005 ÷ 5 = 12201) | 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 | Yes (61005 ÷ 7 = 8715) | 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 3) | 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 61005 a prime number?
No. 61005 = 3 × 5 × × 83, so it is divisible by 3.
What are the factors of 61005?
1, 3, 5, 7, 15, 21, 35, 49, 83, 105, 147, 245, 249, 415, 581, 735, 1245, 1743, 2905, 4067, 8715, 12201, 20335, 61005.
What is 61005 in binary?
1110111001001101 (hexadecimal EE4D, octal 167115).
What is the square root of 61005?
About 246.9919, exactly 7√1245.
Is 61005 divisible by 3?
Yes. Its digits add up to 12, a multiple of 3.
What is special about the number 61005?
It is a composite number with 24 divisors.