13165
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
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 15804
- Proper Divisor Sum (Aliquot Sum)
- 2639
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10528
- Möbius Function
- 1
- Radical
- 13165
- 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
- 138
- 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
- Numbers k such that 5*2^k + 1 is prime.at n=15A002254
- Numbers k such that the continued fraction for sqrt(k) has period 33.at n=37A020372
- Numbers n such that sum of squares of even digits of n equals sum of squares of odd digits of n.at n=12A076164
- Let b(1)=1, b(2)=2, b(n) = sum of digits of b(1)+b(2)+b(3)+...+b(n-1), sequence gives values of n such that b(n)=3.at n=23A084229
- Spt function: total number of smallest parts (counted with multiplicity) in all partitions of n.at n=26A092269
- Sum of digits of n-th even superperfect number A061652(n).at n=20A138827
- Sequence of coefficients of x in marked mesh pattern generating function Q_{n,132}^(3,0,-,0)(x).at n=7A213163
- Numbers n such that 5*2^n + 1 is a prime factor of a generalized Fermat number 3^(2^m) + 1 for some m.at n=3A268661
- Numbers n such that 5*2^n + 1 is a prime factor of a generalized Fermat number 5^(2^m) + 1 for some m.at n=10A268662
- Numbers k such that 5*2^k + 1 is a prime factor of a generalized Fermat number 7^(2^m) + 1 for some m.at n=1A282945
- a(1) = 0, and for n > 1, a(n) = 2*a(A252463(n)) + [n == 1 (mod 2)]*[J(3|n) == -1], where J is the Jacobi-symbol.at n=52A292255
- Numbers k such that (55*10^k + 377)/9 is prime.at n=18A294230
- a(0) = a(1) = a(2) = 1, for n > 2, a(n) = a(n-1) + a(n-k) + k with k = 3.at n=26A362256
- a(n) is the least semiprime > a(n-2) + a(n-1), with a(1) = 4 and a(2) = 6.at n=16A366217