4126
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 6192
- Proper Divisor Sum (Aliquot Sum)
- 2066
- 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
- 2062
- Möbius Function
- 1
- Radical
- 4126
- 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
- 38
- Smith Number
- yes
- 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
- yes
- Odd
- no
Appears in sequences
- A Fielder sequence.at n=13A001642
- Coordination sequence T4 for Zeolite Code BRE.at n=42A008061
- a(n) = n + max_{0 <= i <n} ((n-i)*a(i)), a(0) = 1.at n=19A008609
- Number of increasing sequences of Goldbach type with maximal element n.at n=15A008929
- Coordination sequence for MgCu2, Mg position.at n=16A009931
- Coordination sequence for MgNi2, Position Mg2.at n=16A009935
- Number of partitions of n into distinct parts, none being 3.at n=56A015745
- Numbers k such that the continued fraction for sqrt(k) has period 84.at n=5A020423
- n written in fractional base 7/4.at n=34A024641
- Coordination sequence T1 for Zeolite Code ITE.at n=44A027369
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 64.at n=1A031562
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 38 ones.at n=11A031806
- Numbers whose set of base-11 digits is {1,3}.at n=22A032918
- Digit sum of 'even' number equals digit sum of 'sum' and 'juxtaposition' of its prime factors (counted with multiplicity).at n=42A036926
- Numbers whose base-16 representation has exactly 4 runs.at n=13A043677
- Composite and every divisor (except for 1) contains the digit 2.at n=39A062664
- a(n) = (9*n^2 + 5*n + 2)/2.at n=30A064225
- Consecutive terms of A065966 which are also consecutive integers.at n=14A065976
- Number of subsets S of T={0,1,2,...,n} such that each element of T is the sum of two (not necessarily distinct) elements of S.at n=14A066062
- Prime(a(n)) + ... + prime(a(n)+3) is a square = A051395(n)^2.at n=12A072849