1989
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 3276
- Proper Divisor Sum (Aliquot Sum)
- 1287
- 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
- 1152
- Möbius Function
- 0
- Radical
- 663
- 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
- 24
- 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
- Divisors of 2^24 - 1.at n=42A003532
- States of a dynamic storage system.at n=11A005595
- Number of n-step mappings with 4 inputs.at n=9A005945
- Coordination sequence T3 for Zeolite Code HEU.at n=29A008118
- Partial sums of primes, if 1 is regarded as a prime (as it was until quite recently, see A008578).at n=33A014284
- q-factorial numbers for q=-4.at n=4A015017
- Expansion of Product_{m>=1} (1+x^m)^13.at n=4A022578
- a(n) is least k such that k and 7k are anagrams in base n (written in base 10).at n=19A023099
- a(n) = 1*t(n) + 2*t(n-1) + ...+ k*t(n+1-k), where k=floor((n+1)/2) and t is A001950 (upper Wythoff sequence).at n=19A023867
- s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (natural numbers), t = A001950 (upper Wythoff sequence).at n=18A024864
- Diagonal sum of left-justified array T given by A027023.at n=21A027037
- a(n) = n^2 + n + 9.at n=44A027694
- Numbers whose base-10 representation has 2 fewer 0's than 9's.at n=40A031500
- Numbers whose set of base-6 digits is {1,3}.at n=39A032913
- Numbers each of whose runs of digits in base 12 has length 2.at n=19A033010
- Numbers whose base-12 expansion has no run of digits with length < 2.at n=31A033025
- a(n) = (2*n+1)*(3*n+1)*(4*n+1).at n=4A033591
- Number of partitions of n into parts not of form 4k+2, 8k, 8k+3 or 8k-3.at n=60A036016
- Denominators of continued fraction convergents to sqrt(603).at n=9A042157
- Numbers k such that 8 and 9 occur juxtaposed in the base-10 representation of k but not of k+1.at n=36A044040