7407
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 10712
- Proper Divisor Sum (Aliquot Sum)
- 3305
- 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
- 4932
- Möbius Function
- 0
- Radical
- 2469
- Omega Function (Ω)
- 3
- 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
- 57
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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 g.f. 1/((1-x)*(1-6*x)*(1-8*x)*(1-12*x)).at n=3A024114
- a(n) = s(1)s(n) + s(2)s(n-1) + ... + s(k)s(n+1-k), where k = [ (n+1)/2 ], s = A000201 (lower Wythoff sequence).at n=31A024685
- a(n) = s(1)s(n) + s(2)s(n-1) + ... + s(k)s(n-k+1), where k = [ n/2 ], s = A000201 (lower Wythoff sequence).at n=30A025118
- Trajectory of n under the Reverse and Add! operation carried out in base 4 (presumably) does not reach a palindrome and (presumably) does not join the trajectory of any term m < n.at n=29A075421
- a(n) = smallest k such that the base 4 Reverse and Add! trajectory of A075421(n) joins the trajectory of k.at n=29A091676
- Number of partitions of n into parts each of which is used a different number of times.at n=45A098859
- Records in A111229.at n=29A111270
- Generalized Mancala solitaire (A002491); to get n-th term, start with n and successively round up to next 10 multiples of n-1, n-2, ..., 1, for n>=1.at n=39A113747
- n times n+7 gives the concatenation of two numbers m and m+7.at n=6A116340
- Expansion of Product_{k>=1} (1 + x^k*A005185(k)).at n=23A147879
- a(n) = 529*n + 1.at n=13A158368
- a(n) = 14*n^2 + 1.at n=22A158482
- Positive numbers n such that 8*n^2-2*n-1 divides Fibonacci(n).at n=41A159259
- Numbers n such that n^3 - 4 and n^3 + 4 are prime.at n=30A161589
- INVERT transform of A008805 (triangular numbers repeated).at n=10A178320
- Indices of primes that are the sum of two Fibonacci numbers.at n=35A178971
- G.f.: (1+x^4)/(1-x-x^8).at n=45A193942
- Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 3,2,0,1,4 for x=0,1,2,3,4.at n=3A196583
- Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,2,0,1,4 for x=0,1,2,3,4.at n=3A196586
- T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 3,2,0,1,4 for x=0,1,2,3,4.at n=24A196590