The number 55240
55240 is a composite number with 16 divisors. Its prime factorisation is × 5 × 1381. Divisors (16): 1, 2, 4, 5, 8, 10, 20, 40, 1381, 2762, 5524, 6905, 11048, 13810, 27620, 55240.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 55240: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
55240 is composite. Its prime factorisation is
- 3
The divisors add up to 124380; without 55240 itself that is 69140, so 55240 is abundant (69140 is more than 55240). Euler's totient φ(55240) = 22080 numbers up to 55240 share no factor with it.
- 4
The digits of 55240 add up to 16, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 122 steps to reach 1.
LaTeX source of the formulas on this page
\[ 55240 = 2^{3} \times 5 \times 1381 \]55240 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 124380 |
| Euler totient φ(n) | 22080 |
| Square | 3051457600 |
| Cube | 168562517824000 |
| Square root | 235.031913 (= 2√13810) |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 122 |
| Scientific notation | 5.524 × |
55240 in other forms
| Form | Value |
|---|---|
| In words | fifty-five thousand two hundred and forty |
| Binary (base 2) | 1101011111001000 |
| Octal (base 8) | 153710 |
| Hexadecimal (base 16) | D7C8 |
| Base 3 | 2210202221 |
| As time | 55240 seconds = 15 h 20 min 40 s |
Is 55240 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (55240 ÷ 2 = 27620) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (55240 ÷ 4 = 13810) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (55240 ÷ 5 = 11048) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | 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 (55240 ÷ 8 = 6905) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (55240 ÷ 10 = 5524) | 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 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 55240 a prime number?
No. 55240 = × 5 × 1381, so it is divisible by 2.
What are the factors of 55240?
1, 2, 4, 5, 8, 10, 20, 40, 1381, 2762, 5524, 6905, 11048, 13810, 27620, 55240.
What is 55240 in binary?
1101011111001000 (hexadecimal D7C8, octal 153710).
What is the square root of 55240?
About 235.0319, exactly 2√13810.
Is 55240 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 55240?
55240 is a happy number: repeatedly adding the squares of its digits reaches 1.