4026
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 8928
- Proper Divisor Sum (Aliquot Sum)
- 4902
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 1200
- Möbius Function
- 1
- Radical
- 4026
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- 69
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- Number of partitions of floor(5n/2)-1 into n nonnegative integers each no more than 5.at n=27A001976
- a(n) = ((2*n-1)!/(2*n!*(n-2)!))*((n^3-3*n^2+2*n+2)/(n^2-1)).at n=4A002739
- Number of nonequivalent dissections of an n-gon into 3 polygons by nonintersecting diagonals up to rotation and reflection.at n=42A003453
- Number of ordered triples of integers from [ 2,n ] with no global factor.at n=29A015633
- a(n) is the position of square of n-th prime among the powers of primes (A000961).at n=43A024624
- (d(n)-r(n))/5, where d = A026046 and r is the periodic sequence with fundamental period (1,0,4,0,0).at n=35A026048
- Numbers k such that k^2 is palindromic in base 13.at n=18A029998
- a(n) = prime(n)*prime(n+1) - prime(n).at n=17A037166
- Numbers whose base-4 representation contains exactly three 2's and three 3's.at n=18A045151
- Pisot sequence L(6,7).at n=19A048585
- Pisot sequence L(7,9).at n=18A048589
- a(n) = Sum_{i=0..n} T(i,n-i), array T as in A049687.at n=33A049688
- a(0) = 0; for n>0, a(n) = A005598(n)/2.at n=42A049703
- Starting positions of strings of 2 6's in the decimal expansion of Pi.at n=35A050245
- Partial sums of A051797.at n=7A051878
- Number of nonnegative integer 2 X 2 matrices with no zero rows or columns and with sum of elements equal to n, up to row and column permutation.at n=42A054974
- Numbers k such that k | sigma_5(k).at n=27A055709
- Numbers n such that n^1024 + 1 is prime (a generalized Fermat prime).at n=10A057002
- Multiples of 11 having only even digits.at n=34A061832
- Maximal value of Sum_{i=1..n} (p(i) - p(i+1))^2, where p(n+1) = p(1), as p ranges over all permutations of {1, 2, ..., n}.at n=22A064842