3405
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 5472
- Proper Divisor Sum (Aliquot Sum)
- 2067
- 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
- 1808
- Möbius Function
- -1
- Radical
- 3405
- 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
- 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
- 61
- 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
- no
- Odd
- yes
Appears in sequences
- Number of n-node rooted trees of height 5.at n=12A000342
- Coordination sequence T1 for Zeolite Code EUO.at n=36A008095
- a(n) = floor( n*(n-1)*(n-2)/25 ).at n=45A011907
- a(n) = (d(n)-r(n))/5, where d = A026054 and r is the periodic sequence with fundamental period (3,3,0,0,4).at n=41A026056
- Coordination sequence T1 for Zeolite Code AWO.at n=40A038406
- Denominators of continued fraction convergents to sqrt(229).at n=5A041427
- Denominators of continued fraction convergents to sqrt(916).at n=9A042771
- Numbers whose base-15 representation has exactly 4 runs.at n=14A043671
- Numbers n such that string 0,5 occurs in the base 10 representation of n but not of n-1.at n=36A044337
- Numbers n such that string 0,5 occurs in the base 10 representation of n but not of n+1.at n=36A044718
- Numbers whose base-5 representation contains exactly two 0's and three 1's.at n=35A045168
- Number of ordered pairs of integers (x,y) with x^2+y^2 < n^2.at n=33A051132
- a(n) = Sum_{d|3} phi(d)*n^(3/d).at n=15A054602
- Expansion of e.g.f. cosh(cosh(x)-1) (even powers only).at n=5A059386
- Sum of the reciprocals of the partitions of n enumerated in A058360.at n=40A066824
- Expansion of Product_{i in A069909} 1/(1 - x^i).at n=52A069911
- G.f.: Sum_{k >= 1} x^k/(1-x^k)^(k+1).at n=49A081543
- Triangle T(n, k) read by rows; given by [0, 1, 0, 2, 0, 3, 0, 4, ...] DELTA [1, 0, 2, 0, 2, 0, 3, 0, 2, 0, 4, 0, 2, 0, ...] (A000005 interspersed with 0's) where DELTA is Deléham's operator defined in A084938.at n=39A085852
- a(n) = smallest m >= 1 such that Sum_{k=1..m} log(k)/k >= n.at n=33A092753
- Least number beginning with n such that every partial sum is a square.at n=33A095158