13647
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 18200
- Proper Divisor Sum (Aliquot Sum)
- 4553
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9096
- Möbius Function
- 1
- Radical
- 13647
- 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
- 120
- 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
- Powers of cube root of 3 rounded down.at n=26A017982
- Powers of cube root of 3 rounded to nearest integer.at n=26A017983
- Powers of cube root of 9 rounded down.at n=13A018000
- Powers of cube root of 9 rounded to nearest integer.at n=13A018001
- a(n) = floor(n^3 / Pi).at n=35A032633
- Number of bracelet structures using exactly two different colored beads.at n=19A056357
- 53 'Reverse and Add' steps are needed to reach a palindrome.at n=3A065320
- Numbers n such that n and prime(n) end with the same three digits.at n=10A067841
- 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=33A085703
- Numbers n such that 9*10^n + 7*R_n - 4 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=10A103106
- Numbers n such that in Collatz (3x+1) trajectory of n, the number of terms < n equals number of terms > n.at n=29A217731
- Sum of the fourth largest parts in the partitions of n into 6 parts.at n=44A308870
- Triangle read by rows: T(n,m) (n >= m >= 1) = number of vertices formed by drawing the lines connecting any two of the 2*(m+n) perimeter points of an m X n grid of squares.at n=41A331453
- Number of compositions of n with strictly increasing run-lengths.at n=43A333192
- Triangle T(n,m) = Sum_{k=1..m} C(2*m-k-1,m-k)*C(2*(2*m-k),n-2*m+k), n>0, m>0.at n=49A338036
- Expansion of g.f. Sum_{n>=1} q^n/(1-q^(2*n)-q^(3*n)).at n=37A368689