4201
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 7
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 4202
- 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
- 4200
- Möbius Function
- -1
- Radical
- 4201
- 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
- 64
- 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
- 575
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- G.f.: 1/Product_{k>=1} (1-prime(k)*x^prime(k)).at n=17A002098
- 5th powers written backwards.at n=4A002118
- 10th powers written backwards.at n=2A002241
- 10th powers written backwards.at n=20A002241
- a(n) = n^2 written backwards.at n=31A002942
- Powers of 2 written backwards.at n=10A004094
- Number of n X 3 binary matrices under row and column permutations and column complementations.at n=15A006381
- Primes whose reversal is a square.at n=6A007488
- Coordination sequence T1 for Zeolite Code STI.at n=44A008234
- Expansion of e.g.f. arcsinh(exp(x)*log(x+1)).at n=9A012277
- Next prime after n-th Fibonacci number.at n=19A014208
- Define the sequence S(a_0,a_1) by a_{n+2} is the least integer such that a_{n+2}/a_{n+1}>a_{n+1}/a_n for n >= 0. This is S(4,8).at n=9A019479
- Numbers k such that the continued fraction for sqrt(k) has period 99.at n=0A020438
- a(n) = F(n+3) + c(n) where F(k) is k-th Fibonacci number and c(n) is n-th number that is 1 or 2 or is not a Fibonacci number.at n=15A022809
- Primes that remain prime through 2 iterations of the function f(x) = 8*x + 5.at n=31A023262
- a(n) = b(n) + d(n), where b(n) = (n-th Fibonacci number > 2 ) and d(n) = (n-th number that is 1, 2, or 3, or is not a Lucas number).at n=15A023502
- n written in fractional base 6/4.at n=19A024637
- Numbers whose least quadratic nonresidue (A020649) is 11.at n=24A025024
- a(n) = A026998(2n+1, n+4).at n=3A027007
- a(n) = T(n, 2*n-6), T given by A027960.at n=10A027968