6540
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 18480
- Proper Divisor Sum (Aliquot Sum)
- 11940
- 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
- 1728
- Möbius Function
- 0
- Radical
- 3270
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 4
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
- 44
- 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
- no
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- Number of paraffins.at n=29A005998
- Number of terms in n-th derivative of a function composed with itself 3 times.at n=17A022811
- n written in fractional base 7/6.at n=21A024643
- a(n) = ceiling((n + 7/10)^3).at n=17A034133
- Partial sums of primes congruent to 1 mod 6.at n=35A038349
- Number of primes between n*100000 and (n+1)*100000.at n=41A038825
- Number of partitions satisfying cn(2,5) + cn(3,5) < cn(0,5) + cn(1,5) + cn(4,5).at n=32A039869
- Triangle read by rows: T(n,k) is the number of labeled monoids of order n with k idempotents.at n=12A058157
- Numbers k such that phi(x) = k has exactly 7 solutions.at n=38A060670
- Convolution of A000010 with itself.at n=44A065093
- a(n) = floor(X/Y) where X = concatenation in decreasing order of (2n)-th even number to (n+1)-th even number and Y = that of first n even numbers in increasing order.at n=3A067092
- Numbers k such that k+1 is composite and divides 3^k-2^k.at n=15A068410
- Irregular array, read by rows: T(n,k) is the number of labeled acyclic digraphs with n nodes and k arcs (n >= 0, 0 <= k <= n*(n-1)/2).at n=22A081064
- Numbers n such that numerator(Bernoulli(2*n)/(2*n)) is different from numerator(Bernoulli(2*n)/(2*n*(2*n+1))).at n=23A090177
- Number of consistent sets of 7 irreflexive binary order relationships over n objects.at n=0A147872
- Triangle read by rows, A007318 * (A007476 * 0 ^(n-k)).at n=64A153859
- Triangle, read by rows, T(n, k) = binomial(3*n, 2*k) + binomial(3*n, 2*(n-k)).at n=16A154919
- Triangle, read by rows, T(n, k) = binomial(3*n, 2*k) + binomial(3*n, 2*(n-k)).at n=19A154919
- a(n) = A161330(n)*3.at n=44A161333
- Number of ways to place 3 nonattacking zebras on a 3 X n board.at n=11A172221