7439
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 7656
- Proper Divisor Sum (Aliquot Sum)
- 217
- 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
- 7224
- Möbius Function
- 1
- Radical
- 7439
- 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
- 44
- 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) = n*(4*n+1).at n=43A007742
- Coordination sequence for Ni2In, Position Ni1 and In.at n=26A009941
- Number of partitions satisfying cn(0,5) < cn(1,5) + cn(2,5) + cn(3,5) and cn(0,5) < cn(4,5) + cn(2,5) + cn(3,5).at n=31A039847
- Numerators of continued fraction convergents to sqrt(88).at n=7A041156
- Numbers whose base-5 representation contains exactly three 2's and two 4's.at n=29A045291
- Sum of the quadratic residues of prime(n).at n=39A076409
- a(n) = smallest k such that (10^k-1)/9 == 0 mod prime(n)^2, or 0 if no such k exists.at n=39A087094
- G.f.: A(x) = x/(1 - x - G001190(x^2)), where G001190 is the g.f. of A001190, the Wedderburn-Etherington numbers (binary rooted trees).at n=16A093126
- Numbers n such that p(3n) is prime, where p(n) is the number of partitions of n.at n=40A111389
- Products of two primes that are not Chen primes.at n=17A115719
- Number of permutations of length n which avoid the patterns 231, 4123.at n=10A116703
- Number of permutations of length n which avoid the patterns 1243, 1432, 4213.at n=8A116744
- 2^n + 1 - 2*Fibonacci(n+1).at n=13A119587
- Sum of the quadratic nonresidues of prime(n).at n=39A125615
- Row sums of triangle A137629.at n=26A137630
- 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, 0, 1), (-1, 1, -1), (0, 1, 0), (1, -1, 0)}.at n=10A148129
- 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, 0, 1), (1, 0, 0), (1, 1, -1)}.at n=10A148130
- a(n) = 4*n^2 + 73*n + 333.at n=33A157431
- Number of reducible Boolean polynomials of degree n with constant term 1.at n=16A169914
- Numbers of the form prime(n)*(prime(n)-1)/4.at n=17A171555