10205
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 8
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 13272
- Proper Divisor Sum (Aliquot Sum)
- 3067
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7488
- Möbius Function
- -1
- Radical
- 10205
- 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
- 86
- 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
- Springer numbers associated with symplectic group.at n=7A007836
- Number of partitions of n into prime power parts (1 included); number of nonisomorphic Abelian subgroups of symmetric group S_n.at n=38A023893
- Numbers having three 8's in base 9.at n=36A043487
- Numbers k such that k^8 == 1 (mod 9^3).at n=27A056084
- Sum of the first moments of all partitions of n with weight starting at 1.at n=16A066184
- Consider all Pythagorean triples (X,X+7,Z); sequence gives X values.at n=14A076296
- Total number of parts in all partitions of n into relatively prime parts.at n=22A085410
- Consider the family of multigraphs enriched by the species of cycles. Sequence gives the triangle read by rows giving coefficients of polynomials arising from enumeration of those multigraphs on n edges.at n=30A098283
- Number of topologically connected set partitions of {1,...,n}.at n=10A099947
- Square array T(n,k), read by antidiagonals: number of labeled trees, with increments of labels along edges constrained to -1,0,1, with n nodes that have no label greater than k.at n=50A101486
- a(n) = - a(n-1) - a(n-2) - a(n-3) + 50*(n-4) + 50*a(n-5) + 50*a(n-6) + 50*a(n-7), n >= 8.at n=13A109793
- The values of 'a' in a^2 + b^2 = c^2 where b - a = 7 and gcd(a,b,c)=1.at n=8A117474
- Composite numbers such that the square mean of their prime factors is a nonprime integer (where the prime factors are taken with multiplicity and the square mean of c and d is sqrt((c^2+d^2)/2)).at n=33A134602
- a(n) = 729*n - 1.at n=13A158395
- a(n) = 14*n^2 - 1.at n=26A158485
- Values of hypotenuse of primitive Pythagorean triples which can have four different shapes (that is, four different sets of "legs").at n=36A159781
- Diagonal sum of (100^n,1) Pascal triangle.at n=5A164849
- Composite numbers of form 8n+5 with all prime factors of form 8m+5.at n=42A175486
- Number of -5..5 arrays of n elements with first through fourth differences also in -5..5.at n=4A202661
- T(n,k)=Number of -k..k arrays of n elements with first through fourth differences also in -k..k.at n=40A202664