The number 21316

No. 21316 = 2^2 × 73^2, so it is divisible by 2.

21316 is a perfect square (146²). Its prime factorisation is $2^{2}$ × $73^{2}$ . Divisors (9): 1, 2, 4, 73, 146, 292, 5329, 10658, 21316.

Number

Pick any whole number from 1 to 100,000.

21316 = 2^{2} \times 73^{2}

How to work it out

1
What is special about 21316: a perfect square (146²).
2
21316 is composite. Its prime factorisation is
$21316 = 2^{2} \times 73^{2}$
3
The divisors add up to 37821; without 21316 itself that is 16505, so 21316 is deficient (16505 is less than 21316). Euler's totient φ(21316) = 10512 numbers up to 21316 share no factor with it.
4
The digits of 21316 add up to 13, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 56 steps to reach 1.

LaTeX source of the formulas on this page

\[ 21316 = 2^{2} \times 73^{2} \]

Form	Value
In words	twenty-one thousand three hundred and sixteen
Binary (base 2)	101001101000100
Octal (base 8)	51504
Hexadecimal (base 16)	5344
Base 3	1002020111
As time	21316 seconds = 5 h 55 min 16 s

Divisor	Answer	Rule
2	Yes (21316 ÷ 2 = 10658)	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 (21316 ÷ 4 = 5329)	A number is divisible by 4 if the last two digits make a multiple of 4.
5	No (remainder 1)	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 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	No (remainder 4)	A number is divisible by 8 if the last three digits make a multiple of 8.
9	No (remainder 4)	A number is divisible by 9 if the digits add up to a multiple of 9.
10	No (remainder 6)	A number is divisible by 10 if the last digit is 0.
11	No (remainder 9)	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.

Is 21316 a prime number?

No. 21316 = $2^{2}$ × $73^{2}$ , so it is divisible by 2.

What are the factors of 21316?

1, 2, 4, 73, 146, 292, 5329, 10658, 21316.

What is 21316 in binary?

101001101000100 (hexadecimal 5344, octal 51504).

What is the square root of 21316?

146, because 146 × 146 = 21316.

Is 21316 divisible by 3?

No. Its digits add up to 13, which is not a multiple of 3.

What is special about the number 21316?

21316 is a perfect square (146²).