2179
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 2180
- 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
- 2178
- Möbius Function
- -1
- Radical
- 2179
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 45
- 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
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 327
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Construct a triangle as in A036262. Sequence is one less than the position of the first number larger than 2 in the n-th row (n-th difference).at n=35A000232
- Primes with 7 as smallest primitive root.at n=19A001126
- Primes p such that the multiplicative order of 2 modulo p is (p-1)/3.at n=26A001133
- Wedderburn-Etherington numbers: unlabeled binary rooted trees (every node has outdegree 0 or 2) with n endpoints (and 2n-1 nodes in all).at n=14A001190
- Primes of form n^2 + n + 17.at n=35A007635
- Coefficients of asymptotic expansion of Ramanujan false theta series.at n=8A007779
- Coordination sequence T1 for Zeolite Code ACO, ASV, EDI, and THO.at n=33A008084
- Coordination sequence T7 for Zeolite Code MEL.at n=30A008156
- Coordination sequence T1 for Zeolite Code MFS.at n=29A008173
- Coordination sequence T3 for Zeolite Code MFS.at n=29A008175
- Continued fraction for cube root of 97.at n=72A010325
- Numbers k=3*m+1 such that 2^m == 1 (mod k).at n=53A016108
- Expansion of 1/(1-x^6-x^7-x^8-x^9-x^10-x^11-x^12).at n=43A017852
- Expansion of 1/(1-x^6-x^7-x^8-x^9-x^10-x^11-x^12-x^13).at n=42A017853
- Numbers k such that the continued fraction for sqrt(k) has period 86.at n=0A020425
- Lonely (or isolated) primes: increasing distance to nearest prime.at n=6A023186
- Lonely (or isolated) primes: least prime of distance n from nearest prime (n = 1 or even).at n=9A023188
- Primes that remain prime through 2 iterations of the function f(x) = 2x + 5.at n=32A023243
- Primes that remain prime through 3 iterations of function f(x) = 2x + 5.at n=14A023274
- Primes that remain prime through 4 iterations of function f(x) = 2x + 5.at n=7A023304