5191
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 5400
- Proper Divisor Sum (Aliquot Sum)
- 209
- 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
- 4984
- Möbius Function
- 1
- Radical
- 5191
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- 72
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- yes
- 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
- no
- Odd
- yes
Appears in sequences
- Numbers k such that the continued fraction for sqrt(k) has period 72.at n=12A020411
- a(n) is the position of square of n-th prime among the powers of primes (A000961).at n=47A024624
- Sequence satisfies T^2(a)=a, where T is defined below.at n=47A027588
- Lucky numbers with size of gaps equal to 20 (lower terms).at n=10A031902
- Numbers k such that 105*2^k+1 is prime.at n=34A032402
- Number of 5-ary rooted trees with n nodes and height exactly 5.at n=14A036636
- Sum of first n lucky numbers.at n=46A046279
- Palindromes in factorial base.at n=39A046807
- Numbers k such that sigma(k) divides sigma(k+1), where sigma(k) is sum of positive divisors of k.at n=17A058072
- First (leftmost) digit - second digit + third digit - fourth digit .... = 12.at n=36A061881
- Composite numbers whose divisors (except 1) all contain the digit 9.at n=3A062680
- Dimension of the space of weight n cuspidal newforms for Gamma_1( 59 ).at n=36A063332
- Let p(k) denote k-th prime; consider solutions (n,m) of the Diophantine system {p(p(n)+1)-p(p(n))=2, p(p(n))-6.p(p(m))=-1} (*); sequence gives values of m.at n=19A065511
- Numbers k such that gcd(sigma(k), sigma(k+1)) > k.at n=25A066025
- Numbers k such that sigma(k) divides sigma(phi(k)).at n=28A066831
- Numbers k such that sigma(k+1) = 2*sigma(k).at n=5A067081
- Numbers n such that sigma(phi(n))/sigma(n) = 2.at n=18A067382
- Limit of A069258(k,n) = number of partitions of 2*k into k-n prime parts, as k tends to infinity.at n=34A069259
- Smallest multiple of (n+1)-st prime which is == 1 mod n-th prime.at n=39A073604
- Number of numbers 0 <= m < 10^n which are not the sum of one or more consecutive primes.at n=3A074192