2127
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 2840
- Proper Divisor Sum (Aliquot Sum)
- 713
- 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
- 1416
- Möbius Function
- 1
- Radical
- 2127
- 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
- 76
- Smith Number
- no
- 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
- Let S denote the palindromes in the language {0,1,2}*; a(n) = number of words of length n in the language SS.at n=9A007056
- Sum of the first n primes.at n=34A007504
- Coordination sequence T1 for Zeolite Code AFG.at n=32A008012
- Convolution of Fibonacci numbers and (1, prime(1), prime(2), ...).at n=12A023608
- a(1) = 3; a(n+1) = a(n)-th nonprime, where nonprimes begin at 1.at n=23A025004
- 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 30.at n=18A031528
- Concatenation of n and n + 6 or {n,n+6}.at n=20A032611
- Lucky numbers that are decimal concatenations of n with n + 6.at n=3A032656
- Concatenations C1 and C2 are both prime (see the comment lines).at n=35A034816
- StirlingS2[ n,m ] triangle summed down the columns.at n=31A036560
- Number of partitions satisfying cn(0,5) + cn(1,5) <= cn(2,5) and cn(0,5) + cn(1,5) <= cn(3,5) and cn(0,5) + cn(4,5) <= cn(2,5) and cn(0,5) + cn(4,5) <= cn(3,5).at n=36A039882
- Denominators of continued fraction convergents to sqrt(661).at n=6A042271
- Denominators of continued fraction convergents to sqrt(958).at n=8A042855
- Numbers k such that string 1,7 occurs in the base 8 representation of k but not of k-1.at n=37A044202
- Numbers k such that string 2,3 occurs in the base 9 representation of k but not of k-1.at n=29A044272
- Numbers n such that string 2,7 occurs in the base 10 representation of n but not of n-1.at n=23A044359
- Numbers n such that string 1,1 occurs in the base 8 representation of n but not of n+1.at n=33A044577
- Numbers n such that string 1,7 occurs in the base 8 representation of n but not of n+1.at n=37A044583
- Numbers n such that string 2,3 occurs in the base 9 representation of n but not of n+1.at n=29A044653
- Numbers n such that string 2,7 occurs in the base 10 representation of n but not of n+1.at n=23A044740