The number 5445
5445 is a palindrome: it reads 5445 backwards too. Its prime factorisation is × 5 × . Divisors (18): 1, 3, 5, 9, 11, 15, 33, 45, 55, 99, 121, 165, 363, 495, 605, 1089 … 5445.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 5445: a palindrome: it reads 5445 backwards too; a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
5445 is composite. Its prime factorisation is
- 3
The divisors add up to 10374; without 5445 itself that is 4929, so 5445 is deficient (4929 is less than 5445). Euler's totient φ(5445) = 2640 numbers up to 5445 share no factor with it.
- 4
The digits of 5445 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 54 steps to reach 1.
LaTeX source of the formulas on this page
\[ 5445 = 3^{2} \times 5 \times 11^{2} \]5445 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 18 |
| Sum of divisors | 10374 |
| Euler totient φ(n) | 2640 |
| Square | 29648025 |
| Cube | 161433496125 |
| Square root | 73.790243 (= 33√5) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 54 |
| Scientific notation | 5.445 × |
5445 in other forms
| Form | Value |
|---|---|
| In words | five thousand four hundred and forty-five |
| Binary (base 2) | 1010101000101 |
| Octal (base 8) | 12505 |
| Hexadecimal (base 16) | 1545 |
| Base 3 | 21110200 |
| As time | 5445 seconds = 1 h 30 min 45 s |
Is 5445 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 (5445 ÷ 3 = 1815) | 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 (5445 ÷ 5 = 1089) | 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (5445 ÷ 9 = 605) | 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 | Yes (5445 ÷ 11 = 495) | 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 5445 a prime number?
No. 5445 = × 5 × , so it is divisible by 3.
What are the factors of 5445?
1, 3, 5, 9, 11, 15, 33, 45, 55, 99, 121, 165, 363, 495, 605, 1089, 1815, 5445.
What is 5445 in binary?
1010101000101 (hexadecimal 1545, octal 12505).
What is the square root of 5445?
About 73.7902, exactly 33√5.
Is 5445 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 5445?
5445 is a palindrome: it reads 5445 backwards too; a happy number: repeatedly adding the squares of its digits reaches 1.