4743
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
- 4
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 7488
- Proper Divisor Sum (Aliquot Sum)
- 2745
- 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
- 2880
- Möbius Function
- 0
- Radical
- 1581
- Omega Function (Ω)
- 4
- 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
- 59
- Smith Number
- yes
- 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
- List of pairs of primes in reverse order, starting at 1.at n=7A007796
- Numbers n such that n is a substring of its square in base 5 (written in base 10).at n=12A018829
- Values of A038005 ending in 3.at n=2A038013
- Numbers k such that phi(k) is equal to A008473(k).at n=6A039779
- a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = 2^(p+1) + 2 - n and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1, a(2) = 3, and a(3) = 1.at n=12A049965
- 4n^2+1, 2n^2+1, 2n^2-1 are all prime.at n=16A055755
- Numbers n such that sigma(n)^2 - phi(n)^2 is a perfect square.at n=18A057654
- a(1) = 4; a(n) = smallest composite number of the form k*a(n-1) + 1.at n=37A061766
- Numbers k such that sigma(k^2 + 1) == 0 (mod k).at n=24A067719
- Group successively larger prime numbers so that the sum of the n-th group is a multiple of n. Sequence gives the sum for each group.at n=8A074128
- Numbers k such that phi(k) = Sum_{d|k} core(d) where core(x) is the squarefree part of x (A007913).at n=4A074786
- Numbers n such that A003313(n) = A003313(2n).at n=14A086878
- Numbers n such that (A006530(n) + A020639(n))/2 is an integer, divides n and it is not a power of prime number: it has at least 2 distinct prime factors. Special terms of A088948.at n=35A088595
- Expansion of g.f. (1 + x + 2*x^2)/((1 - x)^3*(1 - x^3)).at n=26A092498
- a(1) = a(2) = 1; for n>2, a(n+1) = a(n) + a(n-1) iff a(n) is prime, otherwise a(n+1) = a(n) + 1.at n=50A113051
- Number of permutations of length n which avoid the patterns 231, 3214, 4312.at n=11A116712
- Array read by antidiagonals: see A128195 for details.at n=25A126062
- a(n) = (2*n + 1)*(a(n - 1) + 2^n) for n >= 1, a(0) = 1.at n=4A128195
- a(n) = (5*n-7)*(n-1).at n=31A147874
- 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), (1, 0, 0), (1, 1, -1)}.at n=9A148230