1023
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 6
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 1536
- Proper Divisor Sum (Aliquot Sum)
- 513
- 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
- 600
- Möbius Function
- -1
- Radical
- 1023
- 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
- 62
- 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
- Number of partitions into non-integral powers.at n=11A000158
- Number of 3-dimensional polyominoes (or polycubes) with n cells.at n=6A000162
- a(n) = 2^n - 1. (Sometimes called Mersenne numbers, although that name is usually reserved for A001348.)at n=10A000225
- Maximum m such that there are no two adjacent elements belonging to the same n-th power residue class modulo some prime p in the sequence 1,2,...,m (equivalently, there is no n-th power residue modulo p in the sequence 1/2,2/3,...,(m-1)/m).at n=8A000236
- a(n) = 4*n^2 - 1.at n=16A000466
- Central factorial numbers: A008955(n,2).at n=3A000596
- Number of 2n-bead balanced binary necklaces of fundamental period 2n, equivalent to reversed complement; also Dirichlet convolution of b_n=2^(n-1) with mu(n); also number of components of Mandelbrot set corresponding to Julia sets with an attractive n-cycle.at n=10A000740
- Double-bitters: only even length runs in binary expansion.at n=31A001196
- Central factorial numbers: 3rd subdiagonal of A008955.at n=2A001821
- Odd squarefree numbers with an odd number of prime factors that have no prime factors greater than 31.at n=43A002556
- Generalized Euler phi function (for p=2).at n=10A003473
- Divisors of 2^10 - 1.at n=7A003523
- Divisors of 2^20 - 1.at n=23A003529
- Divisors of 2^30 - 1.at n=22A003538
- Divisors of 2^40 - 1.at n=33A003546
- Divisors of 2^50 - 1.at n=10A003554
- a(n) = n*(n+2) = (n+1)^2 - 1.at n=31A005563
- a(n) = 3 + n/2 + 7*n^2/2.at n=17A006124
- Continued fraction for 4^5*Sum_{n>=0} 1/4^(2^n).at n=5A006465
- Continued fraction for 4^5*Sum_{n>=0} 1/4^(2^n).at n=3A006465