13201
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 7
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 13552
- Proper Divisor Sum (Aliquot Sum)
- 351
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 12852
- Möbius Function
- 1
- Radical
- 13201
- 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
- 76
- 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
- no
- Odd
- yes
Appears in sequences
- Losing initial positions in game: two players alternate in removing >= 1 stones; last player wins; first player may not remove all stones; each move <= 3 times previous move.at n=28A003411
- a(n) = (n + 3)*(n^2 + 6*n + 2)/6.at n=40A005286
- Bruckman-Lucas pseudoprimes: k | (L_k - 1), where k is composite and L_k = Lucas numbers A000032.at n=8A005845
- Numbers n such that n is a substring of its square in base 5 (written in base 10).at n=16A018829
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 72 ones.at n=15A031840
- Decimal expansion of a(n) is given by the first n terms of the periodic sequence with initial period 1,3,2,0.at n=4A037715
- Denominators of continued fraction convergents to sqrt(143).at n=6A041263
- Composite n coprime to 5 such that Fibonacci(n) == Legendre(n,5) (mod n).at n=7A049062
- a(n) = (F(8*n+7)+F(8*n+5))/3, where F=A000045 (the Fibonacci sequence).at n=2A049679
- a(n) = L(4*n+2)/3, where L=A000032 (the Lucas sequence).at n=5A049685
- Shifts left under transform in formula line.at n=51A052336
- Smallest losing position after your opponent has taken k stones in a variation of "Fibonacci Nim".at n=24A054736
- n written efficiently in natural numbers base, i.e., in form ...wxyz where n = 1*z + 2*y + 3*x + 4*w + ... with z <= 1, y < 2, x < 3, w < 4, ...at n=23A055611
- Primitive part of Fibonacci(n).at n=43A061446
- Primitive part of Lucas(n).at n=21A061447
- Composite numbers k such that k divides F(k-1) where F(j) are the Fibonacci numbers.at n=7A069106
- Sequence arising from factorization of the Fibonacci numbers.at n=43A072183
- Odd Fibonacci pseudoprimes: odd composite numbers k such that either (1) k divides Fibonacci(k-1) if k == +-1 (mod 5) or (2) k divides Fibonacci(k+1) if k == +-2 (mod 5).at n=11A081264
- a(1)=4, then least semiprime > a(n-1) such that when all in the sequence are concatenated together they form a prime.at n=31A085703
- Nonprimes n such that Mod(n,4) == 1 and denominator(Fibonacci((n-1)/4)/n) = 1.at n=3A091982