1656
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 4680
- Proper Divisor Sum (Aliquot Sum)
- 3024
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 528
- Möbius Function
- 0
- Radical
- 138
- Omega Function (Ω)
- 6
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 91
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- yes
- Odd
- no
Appears in sequences
- Triangle of values of 2-d recurrence.at n=68A001404
- Number of partitions of floor(7n/2) into n nonnegative integers each no more than 7.at n=12A001979
- 4th powers written backwards.at n=8A002108
- 8th powers written backwards.at n=3A002232
- Expansion of 1/(1-2*x^2-3*x^3).at n=13A002447
- Denominators of Cauchy numbers of second type (= Bernoulli numbers B_n^{(n)}).at n=22A002790
- Numbers that are the sum of 11 positive 6th powers.at n=26A003367
- Powers of 3 written backwards.at n=8A004167
- a(n) = prime(n) + Fibonacci(n).at n=16A004397
- Coordination sequence T2 for Zeolite Code ATV.at n=26A008044
- Coordination sequence T1 for Zeolite Code FAU.at n=34A008105
- Coordination sequence T1 for Zeolite Code NES.at n=26A008205
- Let j = | i - i_written_backwards |, k = j + j_written_backwards; then k is in this sequence.at n=20A008920
- a(n) = lcm(n, sigma(n)).at n=45A009242
- Coordination sequence for FeS2-Marcasite, S position.at n=20A009954
- Let a,b,c,...k be all divisors of n; a(n) = (a+1)*(b+1)*...*(k+1).at n=21A020696
- a(n) = n*(13*n - 1)/2.at n=16A022270
- Conjectured number of irreducible multiple zeta values of depth 9 and weight 2n+25.at n=8A022497
- n-th 8k+3 prime plus n-th 8k+5 prime.at n=38A022763
- Coordination sequence T2 for Zeolite Code MWW.at n=27A024987