13808
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 10
- Divisor Sum
- 26784
- Proper Divisor Sum (Aliquot Sum)
- 12976
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6896
- Möbius Function
- 0
- Radical
- 1726
- Omega Function (Ω)
- 5
- 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) = n*(27*n - 1)/2.at n=32A022284
- Number of ways of arranging row n of the prime pyramid.at n=15A036440
- a(n) is the first position in the digit sequence 3,1,4,1,5,9,.... of Pi where the pattern "1,2,...,n" occurs (where position of the initial 3 is 1).at n=3A068987
- a(n) = 16*(8*prime(n) + 7).at n=27A098823
- a(n) = 512*n - 16.at n=26A157447
- Number of 2 X 2 nonsingular matrices having all terms in {-n,...,0,...,n}.at n=4A211149
- Nonnegative integers whose English number-words have the identical number of letters contributing to each represented letter-frequency.at n=60A216163
- Number of (n+1) X (1+1) 0..1 arrays with the sum of each 2 X 2 subblock two extreme terms minus its two median terms lexicographically nondecreasing rowwise and columnwise.at n=8A235549
- T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with the sum of each 2X2 subblock two extreme terms minus its two median terms lexicographically nondecreasing rowwise and columnwise.at n=36A235555
- T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with the sum of each 2X2 subblock two extreme terms minus its two median terms lexicographically nondecreasing columnwise and nonincreasing rowwise.at n=36A235772
- Numbers equal to the arithmetic derivative of their Euler totient function.at n=34A248815
- Number of active (ON, black) cells at stage 2^n-1 of the two-dimensional cellular automaton defined by "Rule 133", based on the 5-celled von Neumann neighborhood.at n=6A270233
- Number of partitions of n such that the (sum of distinct even parts) < n/2.at n=35A284616
- Larger of bi-unitary amicable pair.at n=8A292981
- Number of nX5 0..1 arrays with every element equal to 0, 1, 3, 5, 6, 7 or 8 king-move adjacent elements, with upper left element zero.at n=7A300086