6750
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 32
- Divisor Sum
- 18720
- Proper Divisor Sum (Aliquot Sum)
- 11970
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 1800
- Möbius Function
- 0
- Radical
- 30
- Omega Function (Ω)
- 7
- Little Omega Function (ω)
- 3
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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 137
- 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
- yes
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- Expansion of bracket function.at n=13A001659
- G.f.: 2*(1-x^3)/((1-x)^5*(1+x)^2).at n=28A005996
- Expansion of (1-x^5) / (1-x)^5.at n=20A008487
- Triangle of coefficients in expansion of (3+5x)^n.at n=17A013622
- a(n) = (2nd elementary symmetric function of {1/1, 1/2, ..., 1/n})*(lcm(S))^2, where S = {1,2,...,n}.at n=3A025531
- Expansion of 1/((1-4x)(1-5x)(1-7x)(1-11x)).at n=3A028118
- Euler transform of 3 2 1 1 1 1 1 1...at n=16A029859
- a(n) = 2*n^3.at n=15A033431
- a(n) = n*(2*n+5)*(2*n+7).at n=10A035329
- Triangle whose (i,j)-th entry is binomial(i,j)*5^(i-j)*3^j.at n=18A038245
- Expansion of (1-x^2)/(1 - x - 3*x^2 + 2*x^4).at n=12A052933
- Number of connected unlabeled vertex-transitive graphs with n nodes such that complement is also connected.at n=32A054917
- Number of nonnegative integer 3 X 3 matrices with no zero rows or columns and with sum of elements equal to n.at n=8A055005
- Numbers k such that k^128 + 1 is prime.at n=19A056994
- For n>3: a(n) is a multiple of three distinct earlier terms.at n=13A060301
- a(1) = a(2) = a(3) = 1 and a(n) = 24*binomial(n+1, 5) + n*(n^2 - n + 6) for n > 3.at n=8A062027
- Triangle T(n,k) = number of rational (0,1) matrices of rank k (n >= 0, 0 <= k <= n).at n=12A064230
- Number of regions in regular n-gon which are quadrilaterals (4-gons) when all its diagonals are drawn.at n=23A067151
- Triangle formed by multiplying Stirling numbers of 2nd kind S2(n,m) (A008277) by m+1.at n=52A069138
- Expansion of Lambert W function in powers of log(log(x))/log(x).at n=17A073315