1976
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
- 5
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 4200
- Proper Divisor Sum (Aliquot Sum)
- 2224
- 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
- 864
- Möbius Function
- 0
- Radical
- 494
- Omega Function (Ω)
- 5
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 50
- 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
- yes
- Odd
- no
Appears in sequences
- Octagonal numbers: n*(3*n-2). Also called star numbers.at n=26A000567
- Number of primes < prime(n)^2.at n=31A000879
- Generalized octagonal numbers: k*(3*k-2), k=0, +- 1, +- 2, +-3, ...at n=51A001082
- Numbers of the form (p^2 - 49)/120 where p is prime.at n=46A002382
- Numerators of expansion of (1-x)^(-1/3).at n=7A004117
- a(n) = floor(n*phi^9), where phi is the golden ratio, A001622.at n=26A004924
- a(n) = round(n*phi^9), where phi is the golden ratio, A001622.at n=26A004944
- Triangular numbers plus quarter squares: n*(n+1)/2 + floor(n^2/4) (i.e., A000217(n) + A002620(n)).at n=51A006578
- Coordination sequence T1 for Zeolite Code BRE.at n=29A008058
- Coordination sequence T4 for Zeolite Code BRE.at n=29A008061
- If a, b in sequence, so is ab+5.at n=30A009304
- Coordination sequence T6 for Zeolite Code VNI.at n=27A009912
- Let S(x,y) = number of lattice paths from (0,0) to (x,y) that use the step set { (0,1), (1,0), (2,0), (3,0), ....} and never pass below y = x. Sequence gives S(n-3,n).at n=5A010849
- Triangle of numbers S(x,y) = number of lattice paths from (0,0) to (x,y) that use step set { (0,1), (1,0), (2,0), (3,0), ....} and never pass below y = x.at n=41A011117
- a(n) = floor(n*(n-1)*(n-2)/30).at n=40A011912
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly three 1's.at n=28A013650
- Expansion of (1+2*x+3*x^2)/((1-x)*(1-x^2)^2).at n=50A014255
- Even octagonal numbers: a(n) = 4*n*(3*n-1).at n=13A014642
- Numbers k such that phi(k + 12) | sigma(k) for k not congruent to 0 (mod 3).at n=15A015850
- Coordination sequence T5 for Zeolite Code TER.at n=30A016437