6185
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 7428
- Proper Divisor Sum (Aliquot Sum)
- 1243
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4944
- Möbius Function
- 1
- Radical
- 6185
- 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
- 93
- 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
- Expansion of 1/((1-x)*(1-4*x)*(1-8*x)*(1-12*x)).at n=3A021944
- Expansion of Product_{m>=1} (1+m*q^m)^-15.at n=6A022707
- The sequence m(n) in A022905.at n=40A022907
- Number of partitions of n with equal nonzero number of parts congruent to each of 0, 2 and 3 (mod 4).at n=52A046780
- Integers n such that A047988(n)=3.at n=26A047986
- Triangle T(n,k) (n >= 2, k = 3..n+floor(n/2)) giving number of bicoverings of an n-set with k blocks.at n=14A059443
- Number of 5-block bicoverings of an n-set.at n=5A059946
- Use same rules as A047988. Sequence gives smallest numbers which require n steps to reach 2.at n=7A061390
- Interprimes which are of the form s*prime, s=5.at n=16A075280
- Numbers k such that k!!!!! - 1 is prime.at n=48A085149
- Numbers k such that numerator of Sum_{i=1..k} 1/(prime(i)-1) is prime.at n=54A092063
- Numbers k such that k, k+2, k+4, k+6, k+8 are semiprimes.at n=20A092127
- Coefficients of the B-Rogers mod 14 identity.at n=35A105781
- 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, 0, 0), (0, -1, 0), (0, 1, -1), (1, 0, 0), (1, 0, 1)}.at n=7A150397
- 1/4 the number of n X n arrays of squares of integers with every 2X2 subblock summing to 21.at n=9A159222
- Number of nonnegative solutions to x^3 + y^3 + z^3 <= n^3.at n=20A224215
- Number of (n+1) X 4 0..2 matrices with each 2 X 2 subblock idempotent.at n=11A224671
- Number of unlabeled simple graphs with n nodes that are Hamiltonian and integral.at n=7A243273
- Least positive integer k such that (k-1)^2+(k*n)^2, k^2+(k*n-1)^2, (k+1)^2+(k*n)^2 and k^2+(k*n+1)^2 are all prime.at n=28A261382
- Numbers where A262520 takes a negative value; numbers n for which A155043(2n) > A155043(2n + 1).at n=61A262521