1421
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 8
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 1710
- Proper Divisor Sum (Aliquot Sum)
- 289
- 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
- 1176
- Möbius Function
- 0
- Radical
- 203
- 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
- 34
- 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
- no
- Odd
- yes
Appears in sequences
- Coefficient of q^(2n-1) in the series expansion of Ramanujan's mock theta function f(q).at n=30A000199
- Number of permutations of an n-sequence discordant with three given permutations (see reference) in n-3 places.at n=4A000380
- Expansion of 1/(1-x)^2/(1-x^2)/(1-x^6)/(1-x^12)/(1-x^24)/(1-x^48)/(1-x^60).at n=36A001365
- Number of strict 7th-order maximal independent sets in cycle graph.at n=48A007394
- Coordination sequence T1 for Zeolite Code AET.at n=26A008007
- Coordination sequence T1 for Zeolite Code AFI.at n=26A008014
- Coordination sequence T2 for Zeolite Code ATT.at n=27A008042
- Coordination sequence T4 for Zeolite Code DAC.at n=24A008070
- Coordination sequence T2 for Zeolite Code EMT.at n=31A008087
- Coordination sequence T1 for Zeolite Code VFI.at n=29A008245
- Numbers k such that k | 6^k + 1.at n=6A015953
- Numbers k such that k | 13^k + 1.at n=14A015963
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite BOG = Boggsite Na4Ca7[Al18Si78O192].74H2O starting with a T6 atom.at n=10A019078
- Pseudoprimes to base 99.at n=23A020227
- a(n) is least k such that k and 7k are anagrams in base n (written in base 10).at n=22A023099
- Numbers that are the sum of 3 distinct nonzero squares in 10 or more ways.at n=43A025356
- Index of 6^n within the sequence of the numbers of the form 4^i*6^j.at n=46A025714
- Index of 8^n within the sequence of the numbers of the form 5^i*8^j.at n=46A025729
- a(n) = (d(n)-r(n))/5, where d = A026043 and r is the periodic sequence with fundamental period (0,2,3,0,0).at n=24A026045
- Triangular array T read by rows: T(n,1) = T(n,n) = 1, T(n,k) = T(n-1, k-1) + T(n-2,k-1) + T(n-1,k) if k=(n/2) or k=((n+1)/2), otherwise T(n,k) = T(n-1,k-1) + T(n-1,k).at n=60A026703