2164
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
- 6
- Divisor Sum
- 3794
- Proper Divisor Sum (Aliquot Sum)
- 1630
- 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
- 1080
- Möbius Function
- 0
- Radical
- 1082
- Omega Function (Ω)
- 3
- 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
- 45
- 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
- Number of (undirected) Hamiltonian paths in the n-ladder graph K_2 X P_n.at n=46A003682
- Fibonacci numbers written in base 9.at n=17A004692
- Numbers k such that k^64 + 1 is prime.at n=21A006316
- Coordination sequence T3 for Zeolite Code EPI.at n=29A008092
- Coordination sequence T2 for Zeolite Code PAU.at n=34A008220
- Coordination sequence T7 for Zeolite Code PAU.at n=34A008225
- Coordination sequence T8 for Zeolite Code PAU.at n=34A008226
- a(n) = n^2 + n + 2.at n=46A014206
- Numbers k such that the continued fraction for sqrt(k) has period 82.at n=0A020421
- Numbers k such that Fibonacci(k) == 3 (mod k).at n=27A023175
- a(n) = Lucas(n+4) - (3*n+7).at n=11A023537
- Coordination sequence T8 for Zeolite Code MWW.at n=31A024993
- Number of partitions of n into distinct parts >= 2.at n=51A025147
- a(n) = (d(n)-r(n))/2, where d = A026054 and r is the periodic sequence with fundamental period (1,0,0,0).at n=24A026055
- Triangle, T(n, k): T(n,k) = 1 for n < 3, T(3,1) = T(3,2) = T(3,3) = 2, T(n,0) = 1, T(n,1) = n-1, T(n,n) = T(n-1,n-2) + T(n-1,n-1), otherwise T(n,k) = T(n-1,k-2) + T(n-1,k-1) + T(n-1,k), read by rows.at n=63A026268
- Number of (s(0), s(1), ..., s(n)) such that every s(i) is an integer, s(0) = 0, s(1) = 1, s(n) = 2, |s(i) - s(i-1)| <= 1 for i >= 2, |s(2) - s(1)| = 1, |s(3) - s(2)| = 1 if s(2) = 1. Also T(n,n-2), where T is the array in A026268.at n=8A026288
- T(2n+1,n+1), T given by A027011.at n=6A027016
- Duplicate of A023537.at n=11A027962
- 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 22.at n=39A031520
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 42 ones.at n=1A031810