The number 87400
87400 is a composite number with 48 divisors. Its prime factorisation is × × 19 × 23. Divisors (48): 1, 2, 4, 5, 8, 10, 19, 20, 23, 25, 38, 40, 46, 50, 76, 92 … 87400.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 87400: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 19.
- 2
87400 is composite. Its prime factorisation is
- 3
The divisors add up to 223200; without 87400 itself that is 135800, so 87400 is abundant (135800 is more than 87400). Euler's totient φ(87400) = 31680 numbers up to 87400 share no factor with it.
- 4
The digits of 87400 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 120 steps to reach 1.
LaTeX source of the formulas on this page
\[ 87400 = 2^{3} \times 5^{2} \times 19 \times 23 \]87400 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 48 |
| Sum of divisors | 223200 |
| Euler totient φ(n) | 31680 |
| Square | 7638760000 |
| Cube | 667627624000000 |
| Square root | 295.634910 (= 10√874) |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 120 |
| Scientific notation | 8.74 × |
87400 in other forms
| Form | Value |
|---|---|
| In words | eighty-seven thousand four hundred |
| Binary (base 2) | 10101010101101000 |
| Octal (base 8) | 252550 |
| Hexadecimal (base 16) | 15568 |
| Base 3 | 11102220001 |
| As time | 87400 seconds = 24 h 16 min 40 s |
Is 87400 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (87400 ÷ 2 = 43700) | 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 (87400 ÷ 4 = 21850) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (87400 ÷ 5 = 17480) | 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 5) | 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 (87400 ÷ 8 = 10925) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (87400 ÷ 10 = 8740) | 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 | No (remainder 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 87400 a prime number?
No. 87400 = × × 19 × 23, so it is divisible by 2.
What are the factors of 87400?
1, 2, 4, 5, 8, 10, 19, 20, 23, 25, 38, 40, 46, 50, 76, 92, 95, 100, 115, 152, 184, 190, 200, 230, 380, 437, 460, 475, 575, 760, 874, 920, 950, 1150, 1748, 1900, 2185, 2300, 3496, 3800, 4370, 4600, 8740, 10925, 17480, 21850, 43700, 87400.
What is 87400 in binary?
10101010101101000 (hexadecimal 15568, octal 252550).
What is the square root of 87400?
About 295.6349, exactly 10√874.
Is 87400 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 87400?
87400 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 19.