2139
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 3072
- Proper Divisor Sum (Aliquot Sum)
- 933
- 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
- 1320
- Möbius Function
- -1
- Radical
- 2139
- 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
- 76
- 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
- Expansion of 1 / Product_{k>=1} (1-x^k)^(k+1).at n=10A005380
- a(n) = n*(4*n+1).at n=23A007742
- Coordination sequence T3 for Zeolite Code AET.at n=32A008009
- Coordination sequence T3 for Zeolite Code MOR.at n=30A008184
- Fibonacci sequence beginning 3, 13.at n=12A022124
- Sum of squares of numbers in row n of array T given by A026769.at n=6A027245
- Number of partitions of n that do not contain 9 as a part.at n=26A027343
- Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 4.at n=32A031428
- Number of partitions of n into parts 5k+1 or 5k+2.at n=48A035371
- Expansion of g.f. x*(1 + 3*x)/((1 + x)*(1 - x)^3).at n=46A035608
- Number of partitions of n into parts 5k+1 and 5k+4 with at least one part of each type.at n=57A035633
- Minimum area rectangle into which squares of sizes 1, 2, 3, ... n can be packed.at n=17A038666
- Numbers k such that string 3,3 occurs in the base 8 representation of k but not of k-1.at n=33A044214
- Numbers n such that string 3,6 occurs in the base 9 representation of n but not of n-1.at n=29A044284
- Numbers n such that string 3,9 occurs in the base 10 representation of n but not of n-1.at n=23A044371
- Numbers n such that string 3,3 occurs in the base 8 representation of n but not of n+1.at n=33A044595
- Numbers n such that string 3,6 occurs in the base 9 representation of n but not of n+1.at n=29A044665
- Numbers n such that string 1,3 occurs in the base 10 representation of n but not of n+1.at n=24A044726
- Numbers n such that string 3,9 occurs in the base 10 representation of n but not of n+1.at n=23A044752
- 3*n^2-2*n+6.at n=27A047915