Math question: What is the sum of the first five odd numbers greater than 10 and the double of the square root of 28?

To find the sum of the first five odd numbers greater than 10 (11, 13, 15, 17, and 19) and twice the square root of 28, we calculate the sum: 11 + 13 + 15 + 17 + 19 + 2√28. Simplifying, we have 75 + 2√28. By evaluating the square root of 28, which is approximately 5.2915, we find the answer to be 75 + 2(5.2915) = 75 + 10.583 = 85.583 (rounded to three decimal places). Hence, the sum is approximately 85.583.

Math question: What is the sum of all the odd numbers between 1 and 28, inclusive?

To find the answer, we can first determine the number of odd numbers in this range by using the formula (highest number - lowest number) / 2 + 1. In this case, it is (28 - 1) / 2 + 1 = 14 odd numbers. To find the sum, we can use the formula for the sum of an arithmetic series: Sum = (number of terms / 2) * (first term + last term). In this case, the sum can be calculated as (14 / 2) * (1 + 27) = 7 * 28 = 196. Hence, the sum of all odd numbers between 1 and 28 (inclusive) is 196.

Math Question: What is the sum of all integers from 1 to 28?

To find the sum, we can use the formula for the sum of an arithmetic series: Sn = (n/2)(a1 + an), where Sn is the sum, n is the number of terms, a1 is the first term, and an is the last term. In this case, n = 28, a1 = 1, and an = 28. Plugging these values into the formula, we get Sn = (28/2)(1 + 28), which simplifies to Sn = (14)(29) = 406. Therefore, the sum of all integers from 1 to 28 is 406.

Max	9223372036854775807
25835	Positive integer
0b10001100	Binary number
01771452	Octal number
0x129abf	Hex number
5.012 * 10^7	Scientific notation
2^4 * 5	Factorized form
*	Random number

28 (number)

28 is an even 2-digits composite number following 27 and preceding 29. In scientific notation, it is written as 2.8 × 10^1. The sum of its digits is 10. It has a total of 3 prime factors and 6 positive divisors. There are 12 positive integers (up to 28) that are relatively prime to 28.

Interesting facts

28 has 6 divisors, whose sum is 56
The reverse of 28 is 82
Previous prime number is 2

Basic properties

Is Prime? no
Number parity even
Number length 2
Sum of Digits 10
Digital Root 1

Name

Name	twenty-eight

Notation

Scientific notation	2.8 × 10^1
Engineering notation	2.8 × 10^0

Prime Factorization of 28

Prime Factorization 2 × 2 × 7

Composite number

ω	Distinct Factors	2	Total number of distinct prime factors
Ω	Total Factors	3	Total number of prime factors
rad	Radical	14	Product of the distinct prime numbers

The prime factorization of 28 is 2 × 2 × 7. Since it has a total of 3 prime factors.

Most popular turbo-numbers

1, 10, 38, 43, 527, 358, 2644, 908, 29403, 54331, 365747, 831812, 2425992, 9250422, 65577061, 59160456, 386392351, 512400808, 8170407078, 527775585

Basic calculations (n = 28)

Multiplication

n×y

n×2	56
n×3	84
n×4	112
n×5	140

Division

n÷y

n÷2	14
n÷3	9.3333333333333
n÷3	7
n÷5	5.6

Exponentiation

n^y

n²	784
n³	21952
n⁴	614656
n⁵	17210368

Nth Root

^y√n

²√n	5.2915026221292
³√n	3.0365889718757
⁴√n	2.3003266337912
⁵√n	1.9472943612303

Divisors of 28

1, 2, 4, 7, 14, 28

6 divisors

τ	Total Divisors	6	Total number of the positive divisors of n
σ	Sum of Divisors	1	Sum of all the positive divisors of n
s	Aliquot Sum	-27	Sum of the proper positive divisors of n
A	Arithmetic Mean	0.16666666666667	Returns the sum of divisors (σ(n)) divided by the total number of divisors (τ(n))
G	Geometric Mean	1	Returns the nth root of the product of n divisors
H	Harmonic Mean	6	Returns the total number of divisors (τ(n)) divided by the sum of the reciprocal of each divisors

The number 28 can be divided by 6 positive divisors. The sum of these divisors (counting 28) is 1, the average is 0.16666666666667.

Base conversion 28

Base	System	Value
2	Binary	11100
3	Ternary	1001
4	Quaternary	130
5	Quinary	103
6	Senary	44
8	Octal	34
10	Decimal	28
12	Duodecimal	24
16	Hexadecimal	1c
20	Vigesimal	18
36	Base36	s

Cryptographic Hash Functions

md5	33e75ff09dd601bbe69f351039152189
sha1	0a57cb53ba59c46fc4b692527a38a87c78d84028
sha256	59e19706d51d39f66711c2653cd7eb1291c94d9b55eb14bda74ce4dc636d015a
sha512	edbd48c836f826b5ed8d62b401cd19674ef1b8627b9c68a4639819a8564f57426c632b7c1d3dee8209c48c2396da0a3a08d160617f7291a1186ca6d9de5db272
ripemd-160	5c2a4b5773500a0417f6e6d8299776d9cba7ead9

28 as geometric shapes

Circle

Radius = n

Diameter	56
Circumference	175.92918860103
Area	2463.0086404144

Sphere

Radius = n

Volume	91952.322575471
Surface area	9852.0345616576
Circumference	175.92918860103

Square

Length = n

Perimeter	112
Area	784
Diagonal	39.597979746447

Cube

Length = n

Surface area	4704
Volume	21952
Space diagonal	48.497422611929

Equilateral Triangle

Length = n

Perimeter	84
Area	339.4819582835
Altitude	24.248711305964

Triangular Pyramid

Length = n

Surface area	339.4819582835
Volume	2587.0680101012
Height	13.199326582149