The number 42140

Q: Is 42140 a prime number?

No. 42140 = 2^2 × 5 × 7^2 × 43, so it is divisible by 2.

42140 is a composite number with 36 divisors. Its prime factorisation is $2^{2}$ × 5 × $7^{2}$ × 43. Divisors (36): 1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 43, 49, 70, 86, 98, 140 … 42140.

Number

Pick any whole number from 1 to 100,000.

42140 = 2^{2} \times 5 \times 7^{2} \times 43

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How to work it out

1
42140 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
2
42140 is composite. Its prime factorisation is
$42140 = 2^{2} \times 5 \times 7^{2} \times 43$
3
The divisors add up to 105336; without 42140 itself that is 63196, so 42140 is abundant (63196 is more than 42140). Euler's totient φ(42140) = 14112 numbers up to 42140 share no factor with it.
4
The digits of 42140 add up to 11, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 194 steps to reach 1.

LaTeX source of the formulas on this page

\[ 42140 = 2^{2} \times 5 \times 7^{2} \times 43 \]

42140 at a glance

Property	Value
Type	composite
Number of divisors	36
Sum of divisors	105336
Euler totient φ(n)	14112
Square	1775779600
Cube	74831352344000
Square root	205.280296 (= 14√215)
Digit sum / digital root	11 / 2
Collatz steps to 1	194
Scientific notation	4.214 × $10^{4}$

42140 in other forms

Form	Value
In words	forty-two thousand one hundred and forty
Binary (base 2)	1010010010011100
Octal (base 8)	122234
Hexadecimal (base 16)	A49C
Base 3	2010210202
As time	42140 seconds = 11 h 42 min 20 s

Is 42140 divisible by 2 to 12?

Divisor	Answer	Rule
2	Yes (42140 ÷ 2 = 21070)	A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8).
3	No (remainder 2)	A number is divisible by 3 if the digits add up to a multiple of 3.
4	Yes (42140 ÷ 4 = 10535)	A number is divisible by 4 if the last two digits make a multiple of 4.
5	Yes (42140 ÷ 5 = 8428)	A number is divisible by 5 if the last digit is 0 or 5.
6	No (remainder 2)	A number is divisible by 6 if it is divisible by both 2 and 3.
7	Yes (42140 ÷ 7 = 6020)	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 2)	A number is divisible by 9 if the digits add up to a multiple of 9.
10	Yes (42140 ÷ 10 = 4214)	A number is divisible by 10 if the last digit is 0.
11	No (remainder 10)	A number is divisible by 11 if the alternating sum of the digits is a multiple of 11.
12	No (remainder 8)	A number is divisible by 12 if it is divisible by both 3 and 4.

Questions

Is 42140 a prime number?

No. 42140 = $2^{2}$ × 5 × $7^{2}$ × 43, so it is divisible by 2.

What are the factors of 42140?

1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 43, 49, 70, 86, 98, 140, 172, 196, 215, 245, 301, 430, 490, 602, 860, 980, 1204, 1505, 2107, 3010, 4214, 6020, 8428, 10535, 21070, 42140.

What is 42140 in binary?

1010010010011100 (hexadecimal A49C, octal 122234).

What is the square root of 42140?

About 205.2803, exactly 14√215.

Is 42140 divisible by 3?

No. Its digits add up to 11, which is not a multiple of 3.

What is special about the number 42140?

It is a composite number with 36 divisors.