The number 47124

Q: Is 47124 a prime number?

No. 47124 = 2^2 × 3^2 × 7 × 11 × 17, so it is divisible by 2.

47124 is a composite number with 72 divisors. Its prime factorisation is $2^{2}$ × $3^{2}$ × 7 × 11 × 17. Divisors (72): 1, 2, 3, 4, 6, 7, 9, 11, 12, 14, 17, 18, 21, 22, 28, 33 … 47124.

Number

Pick any whole number from 1 to 100,000.

47124 = 2^{2} \times 3^{2} \times 7 \times 11 \times 17

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How to work it out

1
What is special about 47124: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 18.
2
47124 is composite. Its prime factorisation is
$47124 = 2^{2} \times 3^{2} \times 7 \times 11 \times 17$
3
The divisors add up to 157248; without 47124 itself that is 110124, so 47124 is abundant (110124 is more than 47124). Euler's totient φ(47124) = 11520 numbers up to 47124 share no factor with it.
4
The digits of 47124 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 83 steps to reach 1.

LaTeX source of the formulas on this page

\[ 47124 = 2^{2} \times 3^{2} \times 7 \times 11 \times 17 \]

47124 at a glance

Property	Value
Type	composite
Number of divisors	72
Sum of divisors	157248
Euler totient φ(n)	11520
Square	2220671376
Cube	104646917922624
Square root	217.080630 (= 6√1309)
Digit sum / digital root	18 / 9
Collatz steps to 1	83
Scientific notation	4.7124 × $10^{4}$

47124 in other forms

Form	Value
In words	forty-seven thousand one hundred and twenty-four
Binary (base 2)	1011100000010100
Octal (base 8)	134024
Hexadecimal (base 16)	B814
Base 3	2101122100
As time	47124 seconds = 13 h 5 min 24 s

Is 47124 divisible by 2 to 12?

Divisor	Answer	Rule
2	Yes (47124 ÷ 2 = 23562)	A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8).
3	Yes (47124 ÷ 3 = 15708)	A number is divisible by 3 if the digits add up to a multiple of 3.
4	Yes (47124 ÷ 4 = 11781)	A number is divisible by 4 if the last two digits make a multiple of 4.
5	No (remainder 4)	A number is divisible by 5 if the last digit is 0 or 5.
6	Yes (47124 ÷ 6 = 7854)	A number is divisible by 6 if it is divisible by both 2 and 3.
7	Yes (47124 ÷ 7 = 6732)	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 4)	A number is divisible by 8 if the last three digits make a multiple of 8.
9	Yes (47124 ÷ 9 = 5236)	A number is divisible by 9 if the digits add up to a multiple of 9.
10	No (remainder 4)	A number is divisible by 10 if the last digit is 0.
11	Yes (47124 ÷ 11 = 4284)	A number is divisible by 11 if the alternating sum of the digits is a multiple of 11.
12	Yes (47124 ÷ 12 = 3927)	A number is divisible by 12 if it is divisible by both 3 and 4.

Questions

Is 47124 a prime number?

No. 47124 = $2^{2}$ × $3^{2}$ × 7 × 11 × 17, so it is divisible by 2.

What are the factors of 47124?

1, 2, 3, 4, 6, 7, 9, 11, 12, 14, 17, 18, 21, 22, 28, 33, 34, 36, 42, 44, 51, 63, 66, 68, 77, 84, 99, 102, 119, 126, 132, 153, 154, 187, 198, 204, 231, 238, 252, 306, 308, 357, 374, 396, 462, 476, 561, 612, 693, 714, 748, 924, 1071, 1122, 1309, 1386, 1428, 1683, 2142, 2244, 2618, 2772, 3366, 3927, 4284, 5236, 6732, 7854, 11781, 15708, 23562, 47124.

What is 47124 in binary?

1011100000010100 (hexadecimal B814, octal 134024).

What is the square root of 47124?

About 217.0806, exactly 6√1309.

Is 47124 divisible by 3?

Yes. Its digits add up to 18, a multiple of 3.

What is special about the number 47124?

47124 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 18.