15 (number)

15 is an odd 2-digits composite number following 14 and preceding 16. In scientific notation, it is written as 1.5 × 10^1. The sum of its digits is 6. It has a total of 2 prime factors and 4 positive divisors. There are 8 positive integers (up to 15) that are relatively prime to 15.

Interesting facts

Basic properties

Name

Name fifteen

Notation

Scientific notation 1.5 × 10^1
Engineering notation 1.5 × 10^0

Prime Factorization of 15

Prime Factorization 3 × 5

Composite number
ω Distinct Factors 2
Total number of distinct prime factors
Ω Total Factors 2
Total number of prime factors
rad Radical 15
Product of the distinct prime numbers

The prime factorization of 15 is 3 × 5. Since it has a total of 2 prime factors.

Most popular turbo-numbers

5, 7, 69, 27, 731, 428, 8100, 548, 28977, 77156, 328603, 675539, 8941650, 1394890, 37784157, 3387217, 518223260, 725286538, 6040628128, 279362253

Basic calculations (n = 15)

Multiplication

n×y
n×2 30
n×3 45
n×4 60
n×5 75

Division

n÷y
n÷2 7.5
n÷3 5
n÷3 3.75
n÷5 3

Exponentiation

ny
n2 225
n3 3375
n4 50625
n5 759375

Nth Root

y√n
2√n 3.8729833462074
3√n 2.4662120743305
4√n 1.9679896712654
5√n 1.7187719275875

Divisors of 15

1, 3, 5, 15

4 divisors

τ Total Divisors 4
Total number of the positive divisors of n
σ Sum of Divisors 1
Sum of all the positive divisors of n
s Aliquot Sum -14
Sum of the proper positive divisors of n
A Arithmetic Mean 0.25
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 4
Returns the total number of divisors (τ(n)) divided by the sum of the reciprocal of each divisors

The number 15 can be divided by 4 positive divisors. The sum of these divisors (counting 15) is 1, the average is 0.25.

Base conversion 15

Base System Value
2 Binary 1111
3 Ternary 120
4 Quaternary 33
5 Quinary 30
6 Senary 23
8 Octal 17
10 Decimal 15
12 Duodecimal 13
16 Hexadecimal f
20 Vigesimal f
36 Base36 f

Cryptographic Hash Functions

md5 9bf31c7ff062936a96d3c8bd1f8f2ff3
sha1 f1abd670358e036c31296e66b3b66c382ac00812
sha256 e629fa6598d732768f7c726b4b621285f9c3b85303900aa912017db7617d8bdb
sha512 9a6398cffc55ade35b39f1e41cf46c7c491744961853ff9571d09abb55a78976f72c34cd7a8787674efa1c226eaa2494dbd0a133169c9e4e2369a7d2d02de31a
ripemd-160 d6a4bfc37330a92e0bd9df04bb56c566793a900a

15 as geometric shapes

Circle

Radius = n
Diameter 30
Circumference 94.247779607694
Area 706.8583470577

Sphere

Radius = n
Volume 14137.166941154
Surface area 2827.4333882308
Circumference 94.247779607694

Square

Length = n
Perimeter 60
Area 225
Diagonal 21.213203435596

Cube

Length = n
Surface area 1350
Volume 3375
Space diagonal 25.980762113533

Equilateral Triangle

Length = n
Perimeter 45
Area 97.427857925749
Altitude 12.990381056767

Triangular Pyramid

Length = n
Surface area 97.427857925749
Volume 397.74756441743
Height 7.0710678118655