1606
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
- 8
- Divisor Sum
- 2664
- Proper Divisor Sum (Aliquot Sum)
- 1058
- 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
- 720
- Möbius Function
- -1
- Radical
- 1606
- 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
- 21
- 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
- yes
- Odd
- no
Appears in sequences
- a(n) is the solution to the postage stamp problem with n denominations and 4 stamps.at n=15A001214
- Numbers of the form (p^2 - 1)/120 where p is 1 or prime.at n=40A002381
- Number of strongly connected digraphs with n labeled nodes.at n=3A003030
- Numbers that are the sum of 6 positive 5th powers.at n=42A003351
- 9-gonal (or enneagonal) pyramidal numbers: a(n) = n*(n+1)*(7*n-4)/6.at n=11A007584
- Numbers k for which 10k+1, 10k+3, 10k+7 and 10k+9 are primes.at n=14A007811
- Coordination sequence T3 for Zeolite Code ATS.at n=29A008040
- Coordination sequence T1 for Cordierite.at n=24A008251
- Number of n-dimensional partitions of 5.at n=10A008779
- Aliquot sequence starting at 180.at n=48A008891
- Number of 7's in all the partitions of n into distinct parts.at n=52A015742
- Number of partitions of n into distinct parts, none being 7.at n=46A015754
- Coordination sequence T3 for Zeolite Code TER.at n=27A016435
- Define the generalized Pisot sequence T(a(0),a(1)) by: a(n+2) is the greatest integer such that a(n+2)/a(n+1) < a(n+1)/a(n). This is T(8,16).at n=8A018922
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite VET = VPI-8 [Si17O34] starting with a T4 atom.at n=10A019250
- Pseudoprimes to base 81.at n=50A020209
- Convolution of A014306 (starting 0,0,1,1,0,1,1,1,1,...) and primes.at n=32A023674
- a(n) = s(1)*t(n) + s(2)*t(n-1) + ... + s(k)*t(n+1-k), where k = floor((n+1)/2), s = (natural numbers >= 2), t = (Lucas numbers).at n=10A024310
- a(n) = [ (2nd elementary symmetric function of S(n))/(first elementary symmetric function of S(n)) ], where S(n) = {first n+1 positive integers congruent to 1 mod 4}.at n=39A024385
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (odd natural numbers), t = A000201 (lower Wythoff sequence).at n=17A024599