The number 64400
64400 is a composite number with 60 divisors. Its prime factorisation is × × 7 × 23. Divisors (60): 1, 2, 4, 5, 7, 8, 10, 14, 16, 20, 23, 25, 28, 35, 40, 46 … 64400.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 64400: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 14.
- 2
64400 is composite. Its prime factorisation is
- 3
The divisors add up to 184512; without 64400 itself that is 120112, so 64400 is abundant (120112 is more than 64400). Euler's totient φ(64400) = 21120 numbers up to 64400 share no factor with it.
- 4
The digits of 64400 add up to 14, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 73 steps to reach 1.
LaTeX source of the formulas on this page
\[ 64400 = 2^{4} \times 5^{2} \times 7 \times 23 \]64400 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 60 |
| Sum of divisors | 184512 |
| Euler totient φ(n) | 21120 |
| Square | 4147360000 |
| Cube | 267089984000000 |
| Square root | 253.771551 (= 20√161) |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 73 |
| Scientific notation | 6.44 × |
64400 in other forms
| Form | Value |
|---|---|
| In words | sixty-four thousand four hundred |
| Binary (base 2) | 1111101110010000 |
| Octal (base 8) | 175620 |
| Hexadecimal (base 16) | FB90 |
| Base 3 | 10021100012 |
| As time | 64400 seconds = 17 h 53 min 20 s |
Is 64400 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (64400 ÷ 2 = 32200) | 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 (64400 ÷ 4 = 16100) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (64400 ÷ 5 = 12880) | 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 | Yes (64400 ÷ 7 = 9200) | 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 (64400 ÷ 8 = 8050) | 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 | Yes (64400 ÷ 10 = 6440) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 6) | 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 64400 a prime number?
No. 64400 = × × 7 × 23, so it is divisible by 2.
What are the factors of 64400?
1, 2, 4, 5, 7, 8, 10, 14, 16, 20, 23, 25, 28, 35, 40, 46, 50, 56, 70, 80, 92, 100, 112, 115, 140, 161, 175, 184, 200, 230, 280, 322, 350, 368, 400, 460, 560, 575, 644, 700, 805, 920, 1150, 1288, 1400, 1610, 1840, 2300, 2576, 2800, 3220, 4025, 4600, 6440, 8050, 9200, 12880, 16100, 32200, 64400.
What is 64400 in binary?
1111101110010000 (hexadecimal FB90, octal 175620).
What is the square root of 64400?
About 253.7716, exactly 20√161.
Is 64400 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 64400?
64400 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 14.