The number 61664
61664 is a composite number with 24 divisors. Its prime factorisation is × 41 × 47. Divisors (24): 1, 2, 4, 8, 16, 32, 41, 47, 82, 94, 164, 188, 328, 376, 656, 752 … 61664.
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How to work it out
- 1
61664 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
61664 is composite. Its prime factorisation is
- 3
The divisors add up to 127008; without 61664 itself that is 65344, so 61664 is abundant (65344 is more than 61664). Euler's totient φ(61664) = 29440 numbers up to 61664 share no factor with it.
- 4
The digits of 61664 add up to 23, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 55 steps to reach 1.
LaTeX source of the formulas on this page
\[ 61664 = 2^{5} \times 41 \times 47 \]61664 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 127008 |
| Euler totient φ(n) | 29440 |
| Square | 3802448896 |
| Cube | 234474208722944 |
| Square root | 248.322371 (= 4√3854) |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 55 |
| Scientific notation | 6.1664 × |
61664 in other forms
| Form | Value |
|---|---|
| In words | sixty-one thousand six hundred and sixty-four |
| Binary (base 2) | 1111000011100000 |
| Octal (base 8) | 170340 |
| Hexadecimal (base 16) | F0E0 |
| Base 3 | 10010120212 |
| As time | 61664 seconds = 17 h 7 min 44 s |
Is 61664 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (61664 ÷ 2 = 30832) | 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 | Yes (61664 ÷ 4 = 15416) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 4) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 2) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 1) | 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 | Yes (61664 ÷ 8 = 7708) | 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 4) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 61664 a prime number?
No. 61664 = × 41 × 47, so it is divisible by 2.
What are the factors of 61664?
1, 2, 4, 8, 16, 32, 41, 47, 82, 94, 164, 188, 328, 376, 656, 752, 1312, 1504, 1927, 3854, 7708, 15416, 30832, 61664.
What is 61664 in binary?
1111000011100000 (hexadecimal F0E0, octal 170340).
What is the square root of 61664?
About 248.3224, exactly 4√3854.
Is 61664 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 61664?
It is a composite number with 24 divisors.