4122
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 9
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 8970
- Proper Divisor Sum (Aliquot Sum)
- 4848
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 1368
- Möbius Function
- 0
- Radical
- 1374
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 3
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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 126
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- yes
- Odd
- no
Appears in sequences
- Generalized Fibonacci numbers A_{n,4}.at n=32A006209
- n written in fractional base 7/4.at n=30A024641
- Quotient of 'base-23' division described in A032577.at n=52A032578
- Positive numbers having the same set of digits in base 5 and base 10.at n=32A037433
- Concatenate n-th prime and n-th composite.at n=12A038530
- a(n)=(s(n)+6)/10, where s(n)=n-th base 10 palindrome that starts with 4.at n=34A043083
- Numbers whose base-16 representation has exactly 4 runs.at n=9A043677
- T(n,n), array T given by A047000.at n=8A047002
- n*M127 - 1 is prime, where M127 = 2^127 - 1.at n=37A057441
- Number of labeled monoids of order n with a fixed identity.at n=4A058154
- Geometric mean of the digits = 2. In other words, the product of the digits is = 2^k where k is the number of digits.at n=37A061426
- a(n) = (2*n-1)*(5*n^2-5*n+6)/6.at n=13A063489
- Prime(n^2) +/- n are primes.at n=12A064495
- Numbers k such that k divides prime(k) + prime(k+1).at n=11A066895
- Numbers k such that prime(k+1)^2 == prime(k)^2 (mod k).at n=25A067783
- Number of basis partitions of n+64 with Durfee square size 8.at n=19A069251
- a(n) = floor(7^n/6^n).at n=54A094988
- Numbers k such that 5*10^k - 7 is prime.at n=15A103002
- a(1) = 1+2-3 = 0, a(2) = 4+5+6-7 = 8, a(3) = 8+9+10+11-12 = 26, a(4) = 13+14+15+16+17-18 = 57, ...at n=18A111694
- Integers corresponding to rational knots in Conway's enumeration.at n=35A122495