4801
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 4802
- 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
- 4800
- Möbius Function
- -1
- Radical
- 4801
- 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
- 121
- 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
- 647
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- a(n) = 10*a(n-1) - a(n-2); a(0) = 1, a(1) = 5.at n=4A001079
- Primes with 7 as smallest primitive root.at n=41A001126
- Primes p such that the multiplicative order of 2 modulo p is (p-1)/4.at n=31A001134
- Primes of the form 2^q*3^r*5^s + 1.at n=50A002200
- A variant of the cuban primes: primes p = (x^3 - y^3)/(x - y) where x = y + 2.at n=10A002648
- Numbers k such that (11^k - 1)/10 is prime.at n=7A005808
- Smallest odd number expressible in at least n ways as p+2*m^2 where p is 1 or a prime and m >= 0.at n=34A007697
- Smallest odd number expressible in at least n ways as p+2*m^2 where p is 1 or a prime and m >= 0.at n=35A007697
- 3 and -3 are both 4th powers (one implies other) mod these primes p=1 mod 8.at n=33A014755
- Consider all ways of writing a number as p+2m^2 where p is 1 or a prime and m >= 0; sequence gives numbers that are expressible in at least 2 more ways than any smaller number.at n=6A016067
- Numbers k such that the continued fraction for sqrt(k) has period 99.at n=1A020438
- 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=26A024839
- 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=25A024845
- Duplicate of A005808.at n=7A028489
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 38 ones.at n=17A031806
- Primes that do not contain any other prime as a proper substring.at n=35A033274
- Number of partitions of n into parts not of the form 25k, 25k+10 or 25k-10. Also number of partitions with at most 9 parts of size 1 and differences between parts at distance 11 are greater than 1.at n=29A036009
- Maximal base 7 run length is 4.at n=17A037991
- Primes p such that both p-2 and 2p-1 are prime.at n=32A038869
- Primes of form abs(2*n^2-199).at n=45A039950