15829
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 17280
- Proper Divisor Sum (Aliquot Sum)
- 1451
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 14380
- Möbius Function
- 1
- Radical
- 15829
- 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
- 53
- 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 period of the continued fraction for sqrt(k) contains exactly 98 ones.at n=10A031866
- Numbers whose base-4 representation contains exactly four 1's and three 3's.at n=33A045132
- a(1)=1, a(n)=a(n-1)+n^2 if n odd, a(n)=a(n-1)+ n^4 if n is even.at n=9A140150
- Products (semiprimes) of two distinct double-safe primes.at n=9A157356
- Numbers k such that Sum_(i=1..k) prime(i)*(-1)^(i+1) is a square.at n=22A175117
- Number of n X 2 0,1 arrays indicating 2 X 2 subblocks of some larger (n+1) X 3 binary array having determinant equal to one, with rows and columns of the latter in nondecreasing lexicographic order.at n=24A227637
- Numbers n such that n*2^2203 - 1 is prime.at n=21A265503
- Number of n X 3 0..2 arrays with no element equal to any value at offset (-1,0) (0,-1) or (-2,-2) and new values introduced in order 0..2.at n=10A274853
- a(1)=1, a(2)=2; thereafter, denoting x=a(n-1)+a(n-2), we have a(n)=3x+1 if x is odd, otherwise a(n)=x/2^m where 2^m is the maximal power of 2 dividing x.at n=12A276486
- Odd numbers k such that phi(k) and cototient(k) have the same prime signature.at n=18A280927
- Positive numbers k such that -k, -(k + 1), -(k + 2), and -(k + 3) are 4 consecutive negative negabinary-Niven numbers (A331728).at n=9A331825
- Semiprimes k such that k+4, k+6, k+9, k+10 and k+14 are also semiprimes.at n=4A360666
- Numbers k such that k + 4, k + 6, k + 9, k + 10, and k + 14 are all semiprimes, where 4, 6, 9, 10, 14 are the first 5 semiprimes.at n=14A365240
- The five digits of a(n) and their four successive absolute first differences are all distinct.at n=1A365257