2518
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 3780
- Proper Divisor Sum (Aliquot Sum)
- 1262
- 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
- 1258
- Möbius Function
- 1
- Radical
- 2518
- Omega Function (Ω)
- 2
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 84
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- Spiral sieve using Fibonacci numbers.at n=16A005626
- Number of 2n-bead black-white reversible complementable necklaces with n black beads.at n=10A006840
- Number of connected strength-1 Eulerian graphs with n nodes, 2 of odd degree.at n=7A007125
- Coordination sequence T2 for Zeolite Code AFO.at n=33A008016
- Coordination sequence T3 for Zeolite Code MTT.at n=31A008191
- Coordination sequence T4 for Zeolite Code MTW.at n=33A008199
- Coordination sequence T1 for Zeolite Code STI.at n=34A008234
- a(n) = floor(n*(n-1)*(n-2)/13).at n=33A011895
- Convolution of Bell numbers with themselves.at n=7A014322
- Number of triples of different integers from [ 2,n ] with no common factors between pairs.at n=38A015620
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite CHI = Chiavennite Ca4Mn4[Be8Si20O52(OH)8].8H2O starting with a T1 atom.at n=12A019091
- Numbers k such that the continued fraction for sqrt(k) has period 42.at n=22A020381
- a(n) = position of 3*(n^2) in A000408.at n=31A024800
- a(n) = T(n, n-2), T given by A026584. Also a(n) = number of integer strings s(0),...,s(n) counted by T, such that s(n)=2.at n=9A026587
- Number of distinct products i*j*k with 1 <= i < j < k <= n.at n=35A027430
- 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 50.at n=2A031548
- Denominators of continued fraction convergents to sqrt(213).at n=8A041397
- Numbers n such that string 0,7 occurs in the base 9 representation of n but not of n-1.at n=33A044258
- Numbers n such that string 1,8 occurs in the base 10 representation of n but not of n-1.at n=28A044350
- Numbers n such that string 0,7 occurs in the base 9 representation of n but not of n+1.at n=33A044639