13682
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
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 20526
- Proper Divisor Sum (Aliquot Sum)
- 6844
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6840
- Möbius Function
- 1
- Radical
- 13682
- 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
- 58
- 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
- yes
- Odd
- no
Appears in sequences
- Number of points on the surface of 5-dimensional cube.at n=6A008512
- Positive numbers k such that k = x^5 + y^5 has a solution in nonzero integers x, y.at n=36A020896
- a(n) = 7^n - n^5.at n=5A024080
- Becomes prime after exactly 8 iterations of f(x) = sum of prime factors of x.at n=0A047827
- Least number which becomes prime after exactly n iterations of f(x) = sum of prime factors of x.at n=8A047830
- Number of permutations of [1..n] which avoid 4231 and 42513.at n=8A098746
- Number of permutations of length n which avoid the patterns 2143, 2341, 4213.at n=9A116785
- a(n) = 7^n - 5^n.at n=5A121213
- Numbers k such that prime(k)^2 + k! is prime.at n=15A141484
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, -1), (-1, 0, 0), (0, -1, 1), (1, 0, -1), (1, 1, 0)}.at n=9A148798
- Numbers expressible as the difference of two nonnegative fifth powers.at n=23A152045
- Difference of two positive 5th powers.at n=17A181124
- Monotonic ordering of nonnegative differences 7^i-5^j, for 40>= i>=0, j>=0.at n=16A192196
- a(0) = 1, for n > 0: a(n) = Sum_{k=0..n-1} a(k) * (1 + a(n-1-k)).at n=7A215973
- Number of nX6 arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, without 2-loops or left turns.at n=4A221785
- T(n,k)=Number of nXk arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, without 2-loops or left turns.at n=49A221787
- Number of 5 X n arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, without 2-loops or left turns.at n=5A221790
- Numbers which are the sum or difference of two fifth powers.at n=43A247099
- Numbers k such that (29*10^k + 91)/3 is prime.at n=30A269797
- Numbers missing from A001032 despite satisfying the necessary congruence conditions (see comments).at n=32A274469