8023
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 8208
- Proper Divisor Sum (Aliquot Sum)
- 185
- 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
- 7840
- Möbius Function
- 1
- Radical
- 8023
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 189
- Smith Number
- yes
- 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
- Pseudoprimes to base 30.at n=39A020158
- Strong pseudoprimes to base 30.at n=11A020256
- Strong pseudoprimes to base 97.at n=12A020323
- a(n) = 2^n - n^2.at n=13A024012
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 89.at n=8A031587
- Digit sum of 'odd' number equals digit sum of 'sum' and 'juxtaposition' of its prime factors (counted with multiplicity).at n=40A036927
- Numbers whose base-6 representation has exactly 6 runs.at n=21A043614
- Numbers whose base-4 representation contains exactly four 1's and three 3's.at n=16A045132
- Nonnegative numbers of the form x^y - y^x, for x,y > 1.at n=18A045575
- a(n) = 6*n^2 + 6*n + 31.at n=36A060834
- Integers m such that A064992(m) = A064992(m+1).at n=12A065002
- Composite n such that the sums of the composite numbers up to n, +/- 1, are twin primes.at n=43A065022
- Numbers k such that Euler phi(k) / Carmichael lambda(k) = 14.at n=16A066696
- Least nontrivial multiple of the n-th prime beginning with 8.at n=29A078292
- a(n) = 1 + (26*n+17+7*n^2)*n/2.at n=12A095796
- Numbers k such that k^4 = x^3 + y^2 has an integer solution.at n=30A096741
- a(n) = 2^p - p^2 where p is the n-th prime.at n=5A098105
- Semiprimes of the form 2^k - k^2.at n=1A099482
- a(n) = (1/6)*(n^3 + 21*n^2 + 74*n + 18).at n=30A103145
- Start with 1 and repeatedly reverse the digits and add 48 to get the next term.at n=31A118160