2651
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 2904
- Proper Divisor Sum (Aliquot Sum)
- 253
- 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
- 2400
- Möbius Function
- 1
- Radical
- 2651
- 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
- 146
- 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
- Number of n-stacks with strictly receding walls, or the number of Type A partitions of n in the sense of Auluck (1951).at n=30A001522
- a(n) = 2*a(n-1) + 9*a(n-2), with a(0)=a(1)=1.at n=6A002535
- Number of asymmetric planar trees with n nodes.at n=12A005354
- Stella octangula numbers: a(n) = n*(2*n^2 - 1).at n=11A007588
- Coordination sequence T3 for Zeolite Code MEL.at n=33A008152
- Coordination sequence T4 for Zeolite Code NON.at n=31A008215
- Coordination sequence T3 for Zeolite Code STI.at n=35A008236
- Coordination sequence T1 for Zeolite Code TON.at n=32A008241
- Numbers k such that the geometric mean of phi(k) and sigma(k) is an integer.at n=32A011257
- Number of 5-tuples of different integers from [ 1,n ] with no common factors among quadruples.at n=14A015644
- Geometric mean of phi(n) and sigma(n) is an integer, n odd.at n=13A015705
- Positive integers n such that 2^n == 2^11 (mod n).at n=42A015935
- Pseudoprimes to base 36.at n=22A020164
- Pseudoprimes to base 87.at n=22A020215
- Pseudoprimes to base 91.at n=29A020219
- Pseudoprimes to base 98.at n=24A020226
- Strong pseudoprimes to base 91.at n=5A020317
- a(n) = n*(11*n - 1)/2.at n=22A022268
- Numbers k such that Fibonacci(k) == 89 (mod k).at n=34A023182
- a(n) = n*(n^2 + 12*n - 25)/6.at n=22A026057