8265
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
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 14400
- Proper Divisor Sum (Aliquot Sum)
- 6135
- 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
- 4032
- Möbius Function
- 1
- Radical
- 8265
- Omega Function (Ω)
- 4
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 140
- 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
- Expansion of Product (1 - x^k)^10 in powers of x.at n=38A010818
- a(n) = 1*t(n) + 2*t(n-1) + ... + k*t(n+1-k), where k=floor((n+1)/2) and t(n)=2*n+1 (odd numbers).at n=35A023865
- a(n) = s(1)*t(n) + s(2)*t(n-1) + ... + s(k)*t(n-k+1), where k = floor(n/2), s = natural numbers, t = odd natural numbers.at n=34A024862
- Numbers k such that the decimal part of k^(1/7) starts with a 'nine digits' anagram.at n=3A034282
- a(n) = Sum_{k=1..floor((n+1)/2)} T(n,2k-1), array T as in A049777.at n=35A049778
- Numbers n such that sigma(n)^2 - phi(n)^2 is a perfect square.at n=26A057654
- Odd numbers k such that the number of 1's in binary representation of k equals omega(k), the number of distinct primes in the factorization of k.at n=19A071595
- Fifth column (m=4) of (1,3)-Pascal triangle A095660.at n=17A095661
- Number of partitions of n into at least two parts such that the product of largest and smallest part exceeds n.at n=53A116902
- Primitive elements of A119432.at n=15A119433
- Triangle read by rows: T(n,k) is the number of deco polyominoes of height n and having k columns ending at an even level (1<=k<=n). A deco polyomino is a directed column-convex polyomino in which the height, measured along the diagonal, is attained only in the last column.at n=32A121698
- A106486-encodings of combinatorial games equivalent to game {0|1}.at n=34A125997
- a(n) = numerator of Product_{k=1..n} k^mu(n+1-k), where mu(k) = A008683(k).at n=37A130088
- a(n) = n*(n+1)*(8*n + 1)/6.at n=18A132124
- Second bisection of A061041: a(n) = A061041(2n+1) = (2*n+1)*(2*n+9).at n=43A145923
- 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, 1, -1), (-1, 1, 1), (1, 0, 0)}.at n=10A148068
- 5 times hexagonal numbers: 5*n*(2*n-1).at n=29A152745
- Odd squarefree numbers n such that the cyclotomic polynomial Phi(n,x) has height 5.at n=20A152943
- Inverse of A164844.at n=23A164881
- Triangle read by rows: T(n,k) is the number of peakless Motzkin paths of length n having trapezoid weight k (n>=0, k>=0).at n=60A171852