6186
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 12384
- Proper Divisor Sum (Aliquot Sum)
- 6198
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 2060
- Möbius Function
- -1
- Radical
- 6186
- Omega Function (Ω)
- 3
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 124
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- yes
- Odd
- no
Appears in sequences
- a(n) = 1*t(n) + 2*t(n-1) + ... + k*t(n+1-k), where k=floor((n+1)/2) and t = A002808 (composite numbers).at n=34A023863
- Numbers k such that 189*2^k+1 is prime.at n=21A032471
- Number of rooted polygonal cacti (Husimi graphs) with n nodes.at n=14A035082
- Numbers whose base-4 representation contains exactly two 0's and four 2's.at n=15A045051
- Numbers which are the sum of their proper divisors containing the digit 0.at n=36A059461
- Dimension of the space of weight n cuspidal newforms for Gamma_1( 95 ).at n=19A063368
- Numbers beginning and ending with their multiplicative digital root.at n=33A064704
- Numbers n such that sigma(phi(n)) = sum of anti-divisors of n.at n=2A074835
- Indices of primes of the form k^2 - 11.at n=31A091273
- Number of functions of [n] to [n] that simultaneously avoid the patterns 112 and 221.at n=5A093965
- Array read by antidiagonals: number of {112,221}-avoiding words.at n=60A093966
- Numbers k such that the sum of the first k primes is prime and the sum of the squares of the first k primes is also prime.at n=27A124225
- Indices of record values in A046641.at n=40A145772
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, -1), (-1, -1, 1), (-1, 0, 1), (0, 1, -1), (1, 0, 0)}.at n=10A148080
- Number of slanted n X 4 (i=1..n) X (j=i..4+i-1) 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, 4 in the lower right corner, and with no element having more than 2 neighbors with the same value.at n=24A165378
- Number of n X 5 1..2 arrays containing at least one of each value, all equal values connected, rows considered as a single number in nondecreasing order, and columns considered as a single number in nondecreasing order.at n=11A166808
- Sequence defined by the recurrence formula a(n+1)=sum(a(p)*a(n-p)+k,p=0..n)+l for n>=1, with here a(0)=1, a(1)=6, k=0 and l=-2.at n=6A177168
- a(n) = 6*(24*n - 1).at n=42A187206
- Number of nX6 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 0 vertically.at n=2A207715
- T(n,k)=Number of nXk 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 0 vertically.at n=30A207717