1881
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- yes
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 3120
- Proper Divisor Sum (Aliquot Sum)
- 1239
- 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
- 1080
- Möbius Function
- 0
- Radical
- 627
- Omega Function (Ω)
- 4
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 37
- Smith Number
- yes
- 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
- no
- Odd
- yes
Appears in sequences
- Strobogrammatic numbers: the same upside down.at n=22A000787
- Tricapped prism numbers.at n=10A005920
- Numbers with mirror symmetry about middle.at n=13A006072
- Inverse Moebius transform applied twice to squares.at n=38A007433
- Coordination sequence T1 for Zeolite Code ANA.at n=28A008031
- Coordination sequence T2 for Zeolite Code APC.at n=30A008033
- Let j = | i - i_written_backwards |, k = j + j_written_backwards; then k is in this sequence.at n=23A008920
- Coordination sequence T1 for Zeolite Code RSN.at n=28A009885
- Strobogrammatic numbers: numbers that are the same upside down (using calculator-style numerals).at n=46A018846
- Pseudoprimes to base 37.at n=35A020165
- a(n) = n*(31*n + 1)/2.at n=11A022289
- Numbers k such that Fibonacci(k) == 34 (mod k).at n=20A023180
- Generalized Catalan Numbers x^4*A(x)^2 -(1-x+x^4+x^5)*A(x) +1 =0.at n=19A023428
- Positions of squares among the powers of primes (A000961).at n=42A024626
- Positions of cubes among the powers of primes (A000961).at n=14A024627
- a(n) = floor(2nd elementary symmetric function of Sum_{j=1..k} 1/j, k = 1,2,...,n).at n=20A025212
- Numbers that are the sum of 4 distinct positive cubes in exactly 2 ways.at n=18A025409
- Numbers that are the sum of 4 distinct positive cubes in 2 or more ways.at n=19A025412
- a(n) is the smallest number that is the sum of 3 nonzero squares in exactly n ways.at n=17A025414
- Position of 5^n among the powers of primes (A000961).at n=6A025471