6215
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 8208
- Proper Divisor Sum (Aliquot Sum)
- 1993
- 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
- 4480
- Möbius Function
- -1
- Radical
- 6215
- 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
- 62
- 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
- no
- Odd
- yes
Appears in sequences
- a(n) is the number of compositions of n in which the maximum part size is 5.at n=16A006979
- Number of partitions of n into parts not of form 4k+2, 16k, 16k+7 or 16k-7.at n=48A036023
- Number of partitions of n into parts not of form 4k+2, 24k, 24k+7 or 24k-7. Also number of partitions in which no odd part is repeated, with at most 3 parts of size less than or equal to 2 and where differences between parts at distance 5 are greater than 1 when the smallest part is odd and greater than 2 when the smallest part is even.at n=44A036032
- Number of partitions of n such that cn(0,5) = cn(2,5) <= cn(3,5) = cn(4,5) < cn(1,5).at n=55A036847
- Numbers k such that A055079(k) = 2^k.at n=19A057838
- Let v = (1,4,9,...,n^2), x = (0,1,2,4,6,...) [first n terms of A002620]; a(n) = v.v * x.x - (v.x)^2.at n=9A060452
- Consider the line segment in R^n from the origin to the point v = (1,4,9,...,n^2); let d = squared distance to this line from the closest point of Z^n (excluding the endpoints). Sequence gives d times v.v.at n=8A060454
- Triangle read by rows: row n lists number of ordered partitions into k parts of partitions of n.at n=59A060642
- a(n) = min( x : x^3+n^3+x^2+n^2+x+n=1 mod(x+n)).at n=54A066479
- A014486-indices of symmetric binary trees.at n=22A083940
- Total number of parts in all partitions of n into prime parts.at n=46A084993
- Pell pseudoprimes: odd composite numbers n such that P(n)-Kronecker(2,n) is divisible by n.at n=9A099011
- Indices of primes in sequence defined by A(0) = 51, A(n) = 10*A(n-1) + 31 for n > 0.at n=14A101578
- Indices of primes in sequence defined by A(0) = 59, A(n) = 10*A(n-1) - 21 for n > 0.at n=18A101583
- Least k such that prime(n)*(k^2) + prime(n)*k + 1 = m^2 = a square.at n=41A105263
- Numbers n such that every digit occurs at least once in n^3.at n=15A119735
- Triangular array with the first half of the odd-indexed rows of A048004.at n=32A125105
- 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), (-1, 1, -1), (1, 0, 0)}.at n=11A148008
- A sequence of triples of squarefree consecutive integers each composed of exactly three primes.at n=23A165936
- a(n) = (4*n + 3)*(1 + 2*n^2)/3.at n=13A168574