13237
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 15872
- Proper Divisor Sum (Aliquot Sum)
- 2635
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10800
- Möbius Function
- -1
- Radical
- 13237
- 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
- 45
- 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
- Crystal ball sequence for A_8 lattice.at n=3A008392
- Expansion of 1/Sum_{k>=0} (-x)^Fibonacci(k).at n=16A080889
- Half the number of n X n nonnegative integer arrays with every 2 X 2 subblock summing to 2.at n=10A145012
- Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 3X2 zee 1,1 1,2 1,3 2,3 2,4 in any orientation.at n=8A146134
- Products of three distinct primes of the form 6*k + 1.at n=27A154729
- Divisors of 13237.at n=7A163354
- 7 times hexagonal numbers: a(n) = 7*n*(2*n-1).at n=31A195320
- Numbers having exactly four representations by the quadratic form x^2+xy+y^2 with 0<=x<=y.at n=38A198775
- Number of 0..n arrays x(0..8) of 9 elements with zero 5th differences.at n=27A200332
- Number of distinct values of Sum_{i=0..n} x(i)*binomial(n,i), where the x(i) have values in 0..3.at n=13A205538
- Number of 4-bead necklaces labeled with numbers -n..n not allowing reversal, with sum zero and avoiding the patterns z z+1 z+2 and z z-1 z-2.at n=20A209116
- Number of (w,x,y) with all terms in {0,...,n} and x != min(|w-x|, |x-y|).at n=23A213502
- Numbers n such that 7^n + 10 is prime.at n=24A217132
- Composite numbers n such that lambda(n) divides 5n-5, where lambda is the Carmichael lambda function (A002322).at n=37A231572
- Number of partitions p of n such that min(p) + (number of parts of p) is not a part of p.at n=34A238495
- Sum of the middle parts in the partitions of 4n-1 into 3 parts.at n=20A240707
- Number of active (ON, black) cells at stage 2^n-1 of the two-dimensional cellular automaton defined by "Rule 294", based on the 5-celled von Neumann neighborhood.at n=7A271136
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 406", based on the 5-celled von Neumann neighborhood.at n=34A271772
- The icosagen sequence : a(n) = A018227(n)-5, for n >= 2.at n=39A271997
- Square array T(n,k) = number of plane partitions of n with parts colored in (at most) k colors; n, k >= 1; read by antidiagonals.at n=48A306101