13276
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 23240
- Proper Divisor Sum (Aliquot Sum)
- 9964
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6636
- Möbius Function
- 0
- Radical
- 6638
- Omega Function (Ω)
- 3
- 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
- no
- Squarefree Number
- no
- 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
- yes
- Odd
- no
Appears in sequences
- a(n) = 1^2 + prime(1)^2 + prime(2)^2 + ... + prime(n)^2.at n=16A024525
- a(n) = Sum_{i=0..floor(n/2)} A047072(i, n-2*i).at n=23A047079
- Triangle (read by rows) in which the number of entries in a row only increases by 1 every other row, the first column and the 'diagonal' is set to all 1's and a(i,j) = a(i-1,j) + a(i-1,j-1) + a(i-2,j-1) + a(i-3,j-1) for other entries.at n=60A096966
- Number of inequivalent binary sequences of length n, where two sequences are said to be equivalent if they have the same set of phrases in their Ziv-Lempel encodings (the phrases can appear in a different order in the two sequences).at n=25A106182
- Row sums of correlation triangle for floor((n+3)/3).at n=44A115266
- Number of fusenes with 22 hexagons, C_(2h) symmetry and containing 2n carbon atoms.at n=6A123287
- a(-3) = a(-2) = a(-1) = 0, a(0) = 1, a(n) = a(n-1) + 2*a(n-2) + 2*a(n-3) + a(n-4), for n>0.at n=15A123392
- Number of base 16 n-digit numbers with adjacent digits differing by five or less.at n=4A126537
- Number of planar triangular n X n X n nonnegative integer grids with mirror symmetry about one altitude with every similarly oriented 4 X 4 X 4 subtriangle summing to 10.at n=7A154078
- Number of 6X6 arrays of squares of integers, symmetric about both diagonal and antidiagonal, with all rows summing to n.at n=37A156389
- Number of n X n arrays of squares of integers, symmetric about both diagonal and antidiagonal, with all rows summing to 37.at n=4A156501
- Permanent of the n-th principal submatrix of A204255.at n=5A204256
- Numbers n such that if n = a U b (where U denotes concatenation) then sigma*(a) + sigma*(b) = abs(sigma*(n) - n), where sigma*(n) is the sum of the anti-divisors of n.at n=12A239686
- Numbers n such that the decimal expansions of both n and n^2 have 1 as smallest digit and 7 as largest digit.at n=38A257210
- Number of 2Xn arrays containing n copies of 0..2-1 with row sums and column sums nondecreasing.at n=13A267991
- Triangle T(n,p) read by rows: the number of occurrences of p in the restricted growth functions of length n.at n=40A270236
- Sum of the sizes of the fifth blocks in all set partitions of {1,2,...,n}.at n=4A270497
- Sum of the sizes of the (n+1)-th blocks in all set partitions of {1,2,...,2n+1}.at n=4A270529
- G.f.: 1/( (1 - x/(1 - x^2/(1 - x^3/(1 - x^4/(1 - ...))))) * (1 + x/(1 + x^2/(1 + x^3/(1 + x^4/(1 + ...))))) ), a continued fraction.at n=20A285637
- Expansion of Product_{i>=1, j>=1} 1 / (1 - x^(i*j*(j + 1)/2)).at n=27A327744