4049
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 4050
- 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
- 4048
- Möbius Function
- -1
- Radical
- 4049
- 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
- yes
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 558
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of partitions of at most n into at most 5 parts.at n=28A002622
- Primes of form n^2 + n + 17.at n=44A007635
- Coordination sequence T2 for Zeolite Code AFT.at n=48A008027
- Numbers k such that the continued fraction for sqrt(k) has period 49.at n=7A020388
- Primes of the form 36*n^2 - 810*n + 2753, n >= 0, sorted.at n=10A022464
- Least m such that if r and s in {1/4, 1/8, 1/12, ..., 1/4n} satisfy r < s, then r < k/m < (k+1)/m < s for some integer k.at n=24A024839
- a(n) = least m such that if r and s in {1/2, 1/4, 1/6, ..., 1/(2*n)} satisfy r < s, then r < k/m < (k+3)/m < s for some integer k.at n=23A024845
- Primes p such that digits of p appear in p^2 and p^3.at n=26A030085
- Concatenation of n and n + 9 or {n,n+9}.at n=39A032614
- Primes that are decimal concatenations of n with n + 9.at n=6A032632
- Primes of form x^2+62*y^2.at n=31A033240
- Primes that do not contain any other prime as a proper substring.at n=32A033274
- Coordination sequence T3 for Zeolite Code CFI.at n=42A033601
- Primes p such that x^23 = 2 has no solution mod p.at n=27A040984
- Numerators of continued fraction convergents to sqrt(506).at n=3A041966
- Denominators of continued fraction convergents to sqrt(656).at n=10A042261
- Numbers whose base-5 representation contains exactly three 1's and two 4's.at n=28A045261
- Primes with first digit 4.at n=27A045710
- Primes of the form n*phi(n)+1 where phi(n) is the Euler function.at n=37A046062
- p, p+2 and p+8 are primes.at n=35A046134