13091
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 15120
- Proper Divisor Sum (Aliquot Sum)
- 2029
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 11232
- Möbius Function
- -1
- Radical
- 13091
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 3
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
- 138
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- Character of extremal vertex operator algebra of rank 19/2.at n=5A028528
- [ exp(21/22)*n! ].at n=6A030829
- Numbers whose set of base-16 digits is {2,3}.at n=27A032816
- Partial sums of sequence (essentially A002378): 1, 2, 6, 12, 20, 30, 42, 56, 72, 90, ...at n=33A064999
- Centered 22-gonal numbers.at n=34A069173
- Indices of primes in sequence defined by A(0) = 73, A(n) = 10*A(n-1) + 33 for n > 0.at n=16A101148
- Number of 2n-digit primes that are concatenation of n two-digit distinct primes p_1...p_n, 98>p_1>p_2>...>p_n>10.at n=7A168513
- a(n)=(n^4-n^3-n^2-n)/2.at n=13A171129
- Positive integers of the form (10*m^2+1)/11.at n=21A179338
- Number of strings of n numbers x(i) in -1..1 with sums of x(i) and of x(i)*x(i+1) both zero.at n=11A183936
- Number of nonnegative integer arrays of length n+3 with new values 0 upwards introduced in order, and containing the value n-1.at n=7A211563
- a(n) = floor((n+1)*(n-3)*(n-4)/12).at n=56A212772
- Number of partitions p of n such that mean(p) >= multiplicity(min(p)).at n=38A240079
- Number of partitions p = [x(1), ..., x(k)], where x(1) >= x(2) >= ... >= x(k), of n such that max(x(i) - x(i-1)) is a part of p.at n=40A241735
- a(n) = n*(n + 1)*(13*n^2 + 13*n - 14)/24.at n=12A264888
- Numbers k such that both k and k+2 are de Polignac numbers (A006285).at n=16A330284
- Number of entries in the eighth blocks of all set partitions of [n] when blocks are ordered by decreasing lengths.at n=3A333065
- a(n) = a(n-1) + a(n-3) + a(n-4) with initial values a(0) = 8, a(1)=5, a(2) = 13, a(3) = 30.at n=16A347902
- Number of unordered pairs (p,q) of distinct partitions of n such that the set of parts in q is equal to the set of parts in p.at n=26A369697
- Let L_1 = (1) and L_2 = (1, 2); for any n > 2, L_n is obtained by inserting one n between each pair of consecutive terms of L_{n-1} coprime to n; a(n) gives the number of terms in L_n.at n=20A370858