7799
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 32
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 8520
- Proper Divisor Sum (Aliquot Sum)
- 721
- 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
- 7080
- Möbius Function
- 1
- Radical
- 7799
- 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
- 145
- 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
- a(n+1) = 1 + a( floor(n/1) ) + a( floor(n/2) ) + ... + a( floor(n/n) ).at n=37A003318
- Numbers k where |cos(k)| (or |cosec(k)| or |cot(k)|) decreases monotonically to 0; also numbers k where |tan(k)| (or |sec(k)|, or |sin(k)|) increases.at n=27A004112
- Expansion of x*(1+x-x^2)/((1-x)^4*(1+x)).at n=43A005744
- Number of connected posets with n elements of height 1.at n=8A007776
- a(n) = Sum_{j=1..n} j*prime(j).at n=18A014285
- Expansion of Product_{m>=1} (1+q^m)^(-22).at n=4A022617
- Least k such that tan(k) > tan(a(n-1)), for n >= 1, where a(0) = 0.at n=38A024814
- Numbers k where cos(k) decreases monotonically to 0.at n=14A046957
- Numbers k where sin(k) increases monotonically to 1 (or cosec(k) decreases).at n=18A046959
- Numbers k such that 61*2^k-1 is prime.at n=26A050556
- Sum of digits = 8 times number of digits.at n=18A061425
- Numbers k such that floor(tan(k)) > floor(tan(m)) for all m < k.at n=35A063537
- Numbers n such that there exists a block-transitive point-imprimitive 3-design with parameters (k(k-1)/2+1, k, lambda) for some lambda.at n=22A090043
- Expansion of g.f. (1 + x + 2*x^2)/((1 - x)^3*(1 - x^3)).at n=31A092498
- Semiprimes (A001358) made of nontrivial runs of identical digits.at n=17A116063
- a(n) = n*(n^2 - 1)/2 - 1.at n=23A117560
- a(n) = 200*n - 1.at n=38A157955
- a(n) = 78*n^2 - 1.at n=9A158771
- Number of n-digit terms in A048398.at n=16A182781
- G.f.: exp( Sum_{n>=1} sigma(4n)*x^n/n ).at n=7A182820