13027
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 14896
- Proper Divisor Sum (Aliquot Sum)
- 1869
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 11160
- Möbius Function
- 1
- Radical
- 13027
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 45
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- yes
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- f-vectors for simplicial complexes of dimension at most 2 on at most n-1 vertices.at n=12A011827
- f-vectors for 8-neighborly simplicial complexes on n+7 vertices.at n=4A011840
- Number of partitions of n into parts not of the form 25k, 25k+7 or 25k-7. Also number of partitions with at most 6 parts of size 1 and differences between parts at distance 11 are greater than 1.at n=35A036006
- Number of positive integers <= 2^n of form 5 x^2 + 5 y^2.at n=18A054175
- Numbers n such that 2^(n+1)+2n+1 is prime.at n=31A105330
- a(n) is the number of digits in the decimal representation of the smallest Fibonacci number that contains n consecutive identical digits.at n=8A217191
- Cyclops numbers whose squares are cyclops numbers.at n=13A239827
- G.f. A(x) satisfies: 1 - x = Sum_{n>=0} (x^(4*n) + (-1)^n*A(x))^n.at n=22A352820
- Number of regions in a regular 2n-gon when all vertices are connect by straight lines except for the n lines joining diametrically opposite vertices.at n=12A368813
- Number of partitions of prime(n) into squares.at n=39A379551
- a(n) is the number of 4 element sets of integer sided trapezoids with distinct areas and base angles that are 60 degrees, which fill an equilateral triangular grid of side n units.at n=40A389518