7966
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 28
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 13680
- Proper Divisor Sum (Aliquot Sum)
- 5714
- 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
- 3408
- Möbius Function
- -1
- Radical
- 7966
- 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
- 52
- 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
- Expansion of Product_{m >= 1} (1 + q^m)^(-2).at n=54A022597
- a(n) = least m such that if r and s in {1/1, 1/2, 1/3, ..., 1/n} satisfy r < s, then r < k/m < (k+3)/m < s for some integer k.at n=46A024843
- Number of 4n-step self-avoiding closed paths on first quadrant grid, passing through origin, symmetric about line y = x.at n=8A038393
- Numbers whose base-5 representation contains exactly two 2's and three 3's.at n=35A045273
- 23-gonal numbers: a(n) = n(21n-19)/2.at n=28A051875
- a(n) = 4*n^2 - 3*n + 1.at n=45A054552
- Numbers k for which 10*2^k + 3 is a prime (giving terms of A068712).at n=45A068713
- Coefficients of replicable function number "48g".at n=54A073252
- a(0)=1. a(n) = a(n-1) + (largest integer occurring among {a(0),a(1),a(2),...,a(n-1)} that is coprime to n).at n=19A120938
- 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, 0), (-1, 1, 1), (0, 1, -1), (1, 0, 0), (1, 1, -1)}.at n=9A148389
- Triangle read by rows: T(n,k) is the number of Dyck paths of semilength n, having no ascents and no descents of length 1, and having k UUDD's starting at level 0.at n=73A166299
- Number of days after Mar 01 00 such that the date written the format MMDDYY (American standard, short) is palindromic.at n=9A210894
- Number of ordered triples (w,x,y) with all terms in {-n,...-1,1,...,n} and -1<=w+2x+3y<=1.at n=45A211623
- Numbers n such that the sum of the numbers in the Collatz (3x+1) iteration of n is a perfect square.at n=28A225866
- Expansion of phi(x^2) / f(-x) in powers of x where phi(), f() are Ramanujan theta functions.at n=27A226622
- Partial sums of the second power of arithmetic derivative function A003415.at n=29A231864
- Number of partitions of n without three consecutive parts in arithmetic progression.at n=46A238424
- Number of binary strings of length n avoiding the pattern x x x^R (where x^R means reverse of x).at n=48A241903
- a(n) = number of decimal digits of A007505(n).at n=36A275247
- Expansion of e.g.f. sech(x*exp(x)).at n=7A294313