2693
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 2694
- Proper Divisor Sum (Aliquot Sum)
- 1
- 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
- 2692
- Möbius Function
- -1
- Radical
- 2693
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- 66
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- yes
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 392
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Let A(n) = #{(i,j): i^2 + j^2 <= n}, V(n) = Pi*n, P(n) = A(n) - V(n); A000099 gives values of n where |P(n)| sets a new record; sequence gives A(A000099(n)).at n=20A000323
- Primes of the form k^2 + k + 41.at n=47A005846
- Coordination sequence T1 for Zeolite Code BRE.at n=34A008058
- Coordination sequence T3 for Zeolite Code MTT.at n=32A008191
- Coordination sequence T1 for Zeolite Code WEI.at n=37A009917
- Apply partial sum operator thrice to partition numbers.at n=12A014160
- Numbers k such that the continued fraction for sqrt(k) has period 21.at n=20A020360
- Primes that remain prime through 2 iterations of function f(x) = 4x + 9.at n=44A023251
- Primes that remain prime through 2 iterations of the function f(x) = 5x + 4.at n=25A023253
- Primes that remain prime through 2 iterations of function f(x) = 9x + 10.at n=47A023268
- Primes that remain prime through 3 iterations of function f(x) = 4x + 9.at n=10A023282
- a(n) = sum of the numbers between the two n's in A026366.at n=26A026369
- a(n) = Sum_{k=0..n} T(n,n+k), T given by A027023.at n=8A027035
- Dimension of invariant subspace of Lie polynomials of degree 2n under action of SL_2(C) on free Lie algebra of rank 2.at n=10A028351
- a(n) = prime(10*n-8).at n=39A031919
- "DHK[ 6 ]" (bracelet, identity, unlabeled, 6 parts) transform of 1,1,1,1,...at n=15A032247
- Primes of form x^2 + 23*y^2.at n=59A033217
- Number of partitions of n into parts not of the form 15k, 15k+4 or 15k-4. Also number of partitions with at most 3 parts of size 1 and differences between parts at distance 6 are greater than 1.at n=29A035958
- Number of partitions of n into parts not of form 4k+2, 16k, 16k+1 or 16k-1.at n=53A036020
- a(n) is the smallest prime p such that p^2 divides n^(p-1) - 1.at n=11A039951