4581
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
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 6630
- Proper Divisor Sum (Aliquot Sum)
- 2049
- 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
- 3048
- Möbius Function
- 0
- Radical
- 1527
- 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
- 152
- 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
- Coordination sequence T1 for Zeolite Code MEP.at n=40A008157
- Coordination sequence T2 for Zeolite Code -CHI.at n=43A009847
- Numbers k such that the continued fraction for sqrt(k) has period 72.at n=10A020411
- Coordination sequence T4 for Zeolite Code MWW.at n=46A024989
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 28 ones.at n=39A031796
- Multiplicity of highest weight (or singular) vectors associated with character chi_121 of Monster module.at n=36A034509
- Number of partitions of n into parts not of the form 23k, 23k+9 or 23k-9. Also number of partitions with at most 8 parts of size 1 and differences between parts at distance 10 are greater than 1.at n=29A035997
- Sequence arising in search for Legendre sequences.at n=18A039793
- Erroneous version of A028419.at n=12A046664
- a(n)=T(n,n), array T as in A049735.at n=27A049740
- a(n) = a(n-1) + a(m) for n >= 3, 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 and a(2) = 3.at n=37A050069
- Numbers n such that 115*2^n-1 is prime.at n=18A050583
- Number of primes in the interval [prime(n), prime(n)^2].at n=46A054272
- McKay-Thompson series of class 20d for Monster.at n=40A058559
- Rounded total surface area of a regular icosahedron with edge length n.at n=23A071398
- Largest eigenvalue, rounded to the nearest integer, of a rank n matrix of 1..n^2 filled successively along antidiagonals (A069480).at n=19A072332
- a(1)=1; a(n+1) is the smallest integer > a(n) such that Sum_{k=a(n)..a(n+1)} 1/sqrt(k) > Pi.at n=43A073347
- Array T(n,k) read by antidiagonals: expansion of exp(x+y)/(1-xy).at n=50A099597
- Array T(n,k) read by antidiagonals: expansion of exp(x+y)/(1-xy).at n=49A099597
- a(n) is the least number of prime factors in any non-deficient number that has the n-th prime as its least prime factor.at n=44A107705