The number 31020

Q: Is 31020 a prime number?

No. 31020 = 2^2 × 3 × 5 × 11 × 47, so it is divisible by 2.

31020 is a composite number with 48 divisors. Its prime factorisation is $2^{2}$ × 3 × 5 × 11 × 47. Divisors (48): 1, 2, 3, 4, 5, 6, 10, 11, 12, 15, 20, 22, 30, 33, 44, 47 … 31020.

Number

Pick any whole number from 1 to 100,000.

31020 = 2^{2} \times 3 \times 5 \times 11 \times 47

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How to work it out

1
What is special about 31020: a Harshad number: divisible by its digit sum 6.
2
31020 is composite. Its prime factorisation is
$31020 = 2^{2} \times 3 \times 5 \times 11 \times 47$
3
The divisors add up to 96768; without 31020 itself that is 65748, so 31020 is abundant (65748 is more than 31020). Euler's totient φ(31020) = 7360 numbers up to 31020 share no factor with it.
4
The digits of 31020 add up to 6, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 54 steps to reach 1.

LaTeX source of the formulas on this page

\[ 31020 = 2^{2} \times 3 \times 5 \times 11 \times 47 \]

31020 at a glance

Property	Value
Type	composite
Number of divisors	48
Sum of divisors	96768
Euler totient φ(n)	7360
Square	962240400
Cube	29848697208000
Square root	176.124956 (= 2√7755)
Digit sum / digital root	6 / 6
Collatz steps to 1	54
Scientific notation	3.102 × $10^{4}$

31020 in other forms

Form	Value
In words	thirty-one thousand and twenty
Binary (base 2)	111100100101100
Octal (base 8)	74454
Hexadecimal (base 16)	792C
Base 3	1120112220
As time	31020 seconds = 8 h 37 min 0 s

Is 31020 divisible by 2 to 12?

Divisor	Answer	Rule
2	Yes (31020 ÷ 2 = 15510)	A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8).
3	Yes (31020 ÷ 3 = 10340)	A number is divisible by 3 if the digits add up to a multiple of 3.
4	Yes (31020 ÷ 4 = 7755)	A number is divisible by 4 if the last two digits make a multiple of 4.
5	Yes (31020 ÷ 5 = 6204)	A number is divisible by 5 if the last digit is 0 or 5.
6	Yes (31020 ÷ 6 = 5170)	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	No (remainder 4)	A number is divisible by 8 if the last three digits make a multiple of 8.
9	No (remainder 6)	A number is divisible by 9 if the digits add up to a multiple of 9.
10	Yes (31020 ÷ 10 = 3102)	A number is divisible by 10 if the last digit is 0.
11	Yes (31020 ÷ 11 = 2820)	A number is divisible by 11 if the alternating sum of the digits is a multiple of 11.
12	Yes (31020 ÷ 12 = 2585)	A number is divisible by 12 if it is divisible by both 3 and 4.

Questions

Is 31020 a prime number?

No. 31020 = $2^{2}$ × 3 × 5 × 11 × 47, so it is divisible by 2.

What are the factors of 31020?

1, 2, 3, 4, 5, 6, 10, 11, 12, 15, 20, 22, 30, 33, 44, 47, 55, 60, 66, 94, 110, 132, 141, 165, 188, 220, 235, 282, 330, 470, 517, 564, 660, 705, 940, 1034, 1410, 1551, 2068, 2585, 2820, 3102, 5170, 6204, 7755, 10340, 15510, 31020.

What is 31020 in binary?

111100100101100 (hexadecimal 792C, octal 74454).

What is the square root of 31020?

About 176.1250, exactly 2√7755.

Is 31020 divisible by 3?

Yes. Its digits add up to 6, a multiple of 3.

What is special about the number 31020?

31020 is a Harshad number: divisible by its digit sum 6.