4051
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 4052
- 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
- 4050
- Möbius Function
- -1
- Radical
- 4051
- 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
- 157
- 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
- yes
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 559
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of "sets of lists": number of partitions of {1,...,n} into any number of lists, where a list means an ordered subset.at n=6A000262
- a(n) = floor(sinh(n)).at n=9A000471
- a(n) = floor(cosh(n)).at n=9A000501
- Table T(n,k) in which n-th row lists prime factors of 2^n + 1 (n >= 0), with repetition.at n=59A001269
- Primes of the form 2^q*3^r*5^s + 1.at n=49A002200
- Largest prime factor of 2^n + 1.at n=25A002587
- Largest primitive factor of 2^(2n+1) + 1.at n=12A002589
- Divisors of 2^50 - 1.at n=14A003554
- Number of paraffins.at n=20A006001
- Coordination sequence T1 for Zeolite Code ACO, ASV, EDI, and THO.at n=45A008084
- Coordination sequence T4 for Zeolite Code FER.at n=39A008109
- Coordination sequence T2 for Zeolite Code THO.at n=45A008239
- a(n) = floor(n*(n-1)*(n-2)/17).at n=42A011899
- Numbers k such that the continued fraction for sqrt(k) has period 90.at n=1A020429
- Primes that remain prime through 2 iterations of the function f(x) = 8*x + 5.at n=29A023262
- Dying rabbits: a(n) = a(n-1) + a(n-2) - a(n-11).at n=19A023441
- a(n) = least m such that if r and s in {1/2, 1/4, 1/6,..., 1/2n} satisfy r < s, then r < k/m < s for some integer k.at n=50A024820
- 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 63.at n=6A031561
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 30 ones.at n=24A031798
- Primes of form x^2+66*y^2.at n=30A033242