1426
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
- 8
- Divisor Sum
- 2304
- Proper Divisor Sum (Aliquot Sum)
- 878
- 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
- 660
- Möbius Function
- -1
- Radical
- 1426
- Omega Function (Ω)
- 3
- 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
- yes
- 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
- 26
- 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
- Expansion of Product_{m >= 1} (1 + x^m); number of partitions of n into distinct parts; number of partitions of n into odd parts.at n=42A000009
- Pentagonal numbers: a(n) = n*(3*n-1)/2.at n=31A000326
- Expansion of g.f. (1 + x + 2*x^2)/((1 - x)^2*(1 - x^3)).at n=45A000969
- a(1) = a(2) = 1, a(3) = 4; thereafter a(n) = a(n-1) + a(n-3).at n=18A001609
- A generalized partition function.at n=11A002603
- Representation degeneracies for boson strings.at n=22A005293
- Unique period lengths of primes mentioned in A007615.at n=35A007498
- Coordination sequence T1 for Zeolite Code ABW and ATN.at n=26A008000
- Coordination sequence T1 for Zeolite Code BIK.at n=23A008047
- Coordination sequence T3 for Zeolite Code RTH.at n=26A009895
- Coordination sequence T4 for Zeolite Code RTH.at n=26A009896
- Coordination sequence for alpha-Mn, Position Mn1.at n=10A009950
- Even pentagonal numbers.at n=15A014633
- Expansion of 1/(1-x^5-x^6-x^7-x^8-x^9-x^10-x^11-x^12-x^13-x^14).at n=34A017845
- Incorrect version of A035010.at n=6A019275
- Pseudoprimes to base 47.at n=22A020175
- Numbers k such that the continued fraction for sqrt(k) has period 18.at n=44A020357
- a(n) = a(n-1) + c(n) for n >= 3, a( ) increasing, given a(1)=1 a(2)=2; where c( ) is complement of a( ).at n=47A022946
- a(n) = least m such that if r and s in {1/1, 1/2, 1/3, ..., 1/n} satisfy r < s, then r < k/m < (k+3)/m < s for some integer k.at n=19A024843
- Numbers that are the sum of 3 distinct nonzero squares in exactly 8 ways.at n=41A025346