7849
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
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 8064
- Proper Divisor Sum (Aliquot Sum)
- 215
- 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
- 7636
- Möbius Function
- 1
- Radical
- 7849
- 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
- 127
- 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
- Number of connected regular graphs of degree 6 (or sextic graphs) with n nodes.at n=12A006822
- a(n) = n^(n+1) - (n+1)^n.at n=5A007925
- a(n) = 5^n - n^5.at n=6A024054
- (d(n)-r(n))/5, where d = A006527 and r is the periodic sequence with fundamental period (4,1,4,0,1).at n=47A026036
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 60 ones.at n=13A031828
- Nonnegative numbers of the form x^y - y^x, for x,y > 1.at n=17A045575
- Positions of 4-digit terms in the continued fraction for Pi (3 is at position 0).at n=7A048959
- Triangle read by rows: T(n,r) is the number of not necessarily connected r-regular graphs with n nodes, 0 <= r < n.at n=71A051031
- Triangle read by rows: T(n,r) is the number of not necessarily connected r-regular graphs with n nodes, 0 <= r < n.at n=72A051031
- Triangular array C(n, r) = number of connected r-regular graphs with n nodes, 0 <= r < n.at n=72A068934
- Trajectory of n under the Reverse and Add! operation carried out in base 3 (presumably) does not reach a palindrome and (presumably) does not join the trajectory of any term m < n.at n=27A077405
- Triangle read by rows: T(n, k) = abs(n^k-k^n), 1<=k<=n.at n=19A082754
- Semiprimes of the form A007925(n) = n^(n+1)-(n+1)^n.at n=0A099498
- Sum of the quadratic nonresidues of prime(n).at n=38A125615
- a(n) = (n^3 + 3*n - 2)/2.at n=24A132127
- a(n) = 6*n^2 - 10*n + 5.at n=36A136392
- Products (semiprimes) of two distinct double-safe primes.at n=6A157356
- Number of 5-regular graphs (quintic graphs) on 2n vertices.at n=6A165626
- Number of 6-regular graphs (sextic graphs) on n vertices.at n=12A165627
- a(n) = prime(n)^(prime(n)+1) - (prime(n)+1)^prime(n).at n=2A166326