1863
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
- 3
Divisibility
- Divisor Count
- 10
- Divisor Sum
- 2904
- Proper Divisor Sum (Aliquot Sum)
- 1041
- 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
- 1188
- Möbius Function
- 0
- Radical
- 69
- Omega Function (Ω)
- 5
- 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
- 68
- 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
- Bosonic string states.at n=29A005308
- Weighted count of partitions with distinct parts.at n=24A005895
- Number of inequivalent ways (mod D_4) a pair of checkers can be placed on an n X n board.at n=12A014409
- (s(n)+s(n+1))/6, where s()=A006521.at n=11A016059
- (s(n)+s(n+1))/18, where s()=A006521.at n=14A016060
- Number of subsets of { 1, ..., n } containing an arithmetic progression of length 4.at n=12A018789
- Coordination sequence T2 for Zeolite Code CZP.at n=28A019457
- a(n) = n*(7*n + 1)/2.at n=23A022265
- Number of partitions of n into distinct parts >= 3.at n=55A025148
- Numbers that are the sum of 4 distinct positive cubes in exactly 2 ways.at n=17A025409
- Numbers that are the sum of 4 distinct positive cubes in 2 or more ways.at n=18A025412
- Sequence satisfies T(T(a))=a, where T is defined below.at n=48A027581
- Odd n such that in n^2 the parity of digits alternates.at n=48A030155
- 1 together with numbers of the form p*q^4 and p^9, where p and q are distinct primes.at n=39A030628
- Numbers whose base-9 representation has 2 more 0's than 8's.at n=46A031494
- "BHJ" (reversible, identity, labeled) transform of 1,0,1,0... (odds).at n=6A032074
- Numbers whose set of base-11 digits is {1,4}.at n=21A032823
- Number of partitions in parts not of the form 9k, 9k+1 or 9k-1. Also number of partitions with no part of size 1 and differences between parts at distance 3 are greater than 1.at n=37A035940
- Number of partitions satisfying cn(1,5) = cn(4,5) = 0.at n=45A036822
- Numbers k such that k-th and (k+1)-st term of A038593 differ by 2.at n=36A038633