The number 87220

Q: Is 87220 a prime number?

No. 87220 = 2^2 × 5 × 7^2 × 89, so it is divisible by 2.

87220 is a composite number with 36 divisors. Its prime factorisation is $2^{2}$ × 5 × $7^{2}$ × 89. Divisors (36): 1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 49, 70, 89, 98, 140, 178 … 87220.

Number

Pick any whole number from 1 to 100,000.

87220 = 2^{2} \times 5 \times 7^{2} \times 89

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How to work it out

1
87220 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
2
87220 is composite. Its prime factorisation is
$87220 = 2^{2} \times 5 \times 7^{2} \times 89$
3
The divisors add up to 215460; without 87220 itself that is 128240, so 87220 is abundant (128240 is more than 87220). Euler's totient φ(87220) = 29568 numbers up to 87220 share no factor with it.
4
The digits of 87220 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 58 steps to reach 1.

LaTeX source of the formulas on this page

\[ 87220 = 2^{2} \times 5 \times 7^{2} \times 89 \]

87220 at a glance

Property	Value
Type	composite
Number of divisors	36
Sum of divisors	215460
Euler totient φ(n)	29568
Square	7607328400
Cube	663511183048000
Square root	295.330324 (= 14√445)
Digit sum / digital root	19 / 1
Collatz steps to 1	58
Scientific notation	8.722 × $10^{4}$

87220 in other forms

Form	Value
In words	eighty-seven thousand two hundred and twenty
Binary (base 2)	10101010010110100
Octal (base 8)	252264
Hexadecimal (base 16)	154B4
Base 3	11102122101
As time	87220 seconds = 24 h 13 min 40 s

Is 87220 divisible by 2 to 12?

Divisor	Answer	Rule
2	Yes (87220 ÷ 2 = 43610)	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 (87220 ÷ 4 = 21805)	A number is divisible by 4 if the last two digits make a multiple of 4.
5	Yes (87220 ÷ 5 = 17444)	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	Yes (87220 ÷ 7 = 12460)	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 1)	A number is divisible by 9 if the digits add up to a multiple of 9.
10	Yes (87220 ÷ 10 = 8722)	A number is divisible by 10 if the last digit is 0.
11	No (remainder 1)	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 87220 a prime number?

No. 87220 = $2^{2}$ × 5 × $7^{2}$ × 89, so it is divisible by 2.

What are the factors of 87220?

1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 49, 70, 89, 98, 140, 178, 196, 245, 356, 445, 490, 623, 890, 980, 1246, 1780, 2492, 3115, 4361, 6230, 8722, 12460, 17444, 21805, 43610, 87220.

What is 87220 in binary?

10101010010110100 (hexadecimal 154B4, octal 252264).

What is the square root of 87220?

About 295.3303, exactly 14√445.

Is 87220 divisible by 3?

No. Its digits add up to 19, which is not a multiple of 3.

What is special about the number 87220?

It is a composite number with 36 divisors.