The number 15240
15240 is a composite number with 32 divisors. Its prime factorisation is × 3 × 5 × 127. Divisors (32): 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120 … 15240.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 15240: a Harshad number: divisible by its digit sum 12.
- 2
15240 is composite. Its prime factorisation is
- 3
The divisors add up to 46080; without 15240 itself that is 30840, so 15240 is abundant (30840 is more than 15240). Euler's totient φ(15240) = 4032 numbers up to 15240 share no factor with it.
- 4
The digits of 15240 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 40 steps to reach 1.
LaTeX source of the formulas on this page
\[ 15240 = 2^{3} \times 3 \times 5 \times 127 \]15240 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 32 |
| Sum of divisors | 46080 |
| Euler totient φ(n) | 4032 |
| Square | 232257600 |
| Cube | 3539605824000 |
| Square root | 123.450395 (= 2√3810) |
| Digit sum / digital root | 12 / 3 |
| Collatz steps to 1 | 40 |
| Scientific notation | 1.524 × |
15240 in other forms
| Form | Value |
|---|---|
| In words | fifteen thousand two hundred and forty |
| Binary (base 2) | 11101110001000 |
| Octal (base 8) | 35610 |
| Hexadecimal (base 16) | 3B88 |
| Base 3 | 202220110 |
| As time | 15240 seconds = 4 h 14 min 0 s |
Is 15240 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (15240 ÷ 2 = 7620) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (15240 ÷ 3 = 5080) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (15240 ÷ 4 = 3810) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (15240 ÷ 5 = 3048) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (15240 ÷ 6 = 2540) | 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 (15240 ÷ 8 = 1905) | 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 | Yes (15240 ÷ 10 = 1524) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | Yes (15240 ÷ 12 = 1270) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 15240 a prime number?
No. 15240 = × 3 × 5 × 127, so it is divisible by 2.
What are the factors of 15240?
1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120, 127, 254, 381, 508, 635, 762, 1016, 1270, 1524, 1905, 2540, 3048, 3810, 5080, 7620, 15240.
What is 15240 in binary?
11101110001000 (hexadecimal 3B88, octal 35610).
What is the square root of 15240?
About 123.4504, exactly 2√3810.
Is 15240 divisible by 3?
Yes. Its digits add up to 12, a multiple of 3.
What is special about the number 15240?
15240 is a Harshad number: divisible by its digit sum 12.