2740
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
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 5796
- Proper Divisor Sum (Aliquot Sum)
- 3056
- 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
- 1088
- Möbius Function
- 0
- Radical
- 1370
- Omega Function (Ω)
- 4
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 128
- 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 two-rowed partitions of length 3.at n=27A001993
- a(n) = n^3 - floor( n/3 ).at n=14A002901
- Inversion of A000257.at n=6A004040
- a(n) = 1 + Sum_{i=1..n} (n-i+1)*phi(i).at n=29A005598
- Number of points on surface of tetrahedron; coordination sequence for sodalite net (equals 2*n^2+2 for n > 0).at n=37A005893
- Coordination sequence T3 for Zeolite Code DAC.at n=33A008069
- Coordination sequence T1 for Zeolite Code ACO, ASV, EDI, and THO.at n=37A008084
- Coordination sequence T2 for Zeolite Code EDI.at n=37A008085
- a(n) = floor( n*(n-1)*(n-2)/8 ).at n=29A011890
- a(n) = floor( n*(n-1)*(n-2)/29 ).at n=44A011911
- Powers of fifth root of 21 rounded down.at n=13A018174
- Powers of fifth root of 21 rounded to nearest integer.at n=13A018175
- Numbers k such that the continued fraction for sqrt(k) has period 34.at n=28A020373
- Conjectured number of irreducible multiple zeta values of depth 9 and weight 2n+25.at n=9A022497
- Number of permutations of length n avoiding the pattern 1342.at n=7A022558
- a(n) = Sum_{k=1..n} k*floor( prime(k)/k ).at n=39A024927
- a(n) = (d(n)-r(n))/5, where d = A026057 and r is the periodic sequence with fundamental period (1,0,3,1,0).at n=36A026059
- Numbers k such that Hofstadter Q-sequence Q(k) (A005185) satisfies Q(k) = k/2.at n=36A027619
- n^3*a(n) is the number of circles in complex projective plane tangent to three smooth curves of degree n in general position.at n=12A030653
- Numbers having period-1 5-digitized sequences.at n=35A031187