1285
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 1548
- Proper Divisor Sum (Aliquot Sum)
- 263
- 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
- 1024
- Möbius Function
- 1
- Radical
- 1285
- Omega Function (Ω)
- 2
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 26
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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 free polyominoes (or square animals) with n cells.at n=9A000105
- Moser-de Bruijn sequence: sums of distinct powers of 4.at n=51A000695
- Sierpiński's triangle (Pascal's triangle mod 2) converted to decimal.at n=10A001317
- Number of partitions of n into at most 4 parts.at n=52A001400
- Sum of 10 nonzero 8th powers.at n=5A003388
- Numbers of edges of regular polygons constructible with ruler (or, more precisely, an unmarked straightedge) and compass.at n=59A003401
- Divisors of 2^16 - 1.at n=10A003527
- Divisors of 2^32 - 1 (for a(1) to a(31), the 31 regular polygons with an odd number of sides constructible with ruler and compass).at n=10A004729
- Sequence and first differences (A030124) together list all positive numbers exactly once.at n=45A005228
- Number of parallelogram polyominoes with n cells (also called staircase polyominoes, although that term is overused).at n=9A006958
- For any circular arrangement of 0..n-1, let S = sum of squares of every sum of two contiguous numbers; then a(n) = # of distinct values of S.at n=19A007773
- Crystal ball sequence for diamond.at n=11A007904
- Coordination sequence T4 for Zeolite Code DOH.at n=22A008081
- Coordination sequence T3 for Zeolite Code LTN.at n=25A008142
- Number of ZnS polytypes that repeat after n layers.at n=16A011957
- Number of partitions of 2*n into at most 4 parts.at n=26A014126
- Number of (unordered) triples of integers from [1,n] with no common factors between pairs.at n=29A015617
- Number of triples of different integers from [ 2,n ] with no common factors between pairs.at n=29A015620
- Positive integers n such that 2^n == 2^5 (mod n).at n=43A015925
- Expansion of 1/(1-x^3-x^4-x^5-x^6-x^7).at n=25A017820