15898
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 31
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 23850
- Proper Divisor Sum (Aliquot Sum)
- 7952
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7948
- Möbius Function
- 1
- Radical
- 15898
- 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
- 97
- Smith Number
- yes
- 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
- yes
- Odd
- no
Appears in sequences
- Numbers k such that the continued fraction for sqrt(k) has period 81.at n=15A020420
- Numbers k such that 2^k + 3^k is a semiprime.at n=32A050244
- Self-convolution of A086582; the first 2^n terms of this sequence gives the 2^n terms that follow the 2^n-th term of A086582.at n=46A086583
- Number of square plane partitions of n.at n=33A089299
- Numbers m such that numerator of Sum_{k=1..m} 1/(prime(k)-k) is prime.at n=48A092065
- E.g.f. satisfies A(x) = exp(x + x^2/2 * A(x)).at n=7A143740
- Numbers k such that (2^k + 3^k)/13 is prime.at n=14A181628
- Number of intervals in the weak (Bruhat) order of the symmetric group S_n that are distributive lattices.at n=5A190291
- Number of (n+1)X(2+1) 0..3 arrays with the maximum plus the minimum minus the lower median of every 2X2 subblock equal.at n=1A237483
- T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with the maximum plus the minimum minus the lower median of every 2X2 subblock equal.at n=4A237488
- Indices of Wagstaff primes.at n=6A243979
- Number of compositions (ordered partitions) of n into odd primes (including 1).at n=22A309676
- Number of integer partitions of n whose Heinz number (product of primes of parts) is divisible by all parts.at n=44A330952
- Number of integer partitions of n such that neither the run-lengths nor the negated run-lengths are unimodal.at n=42A332640
- Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,k) = n! * Sum_{j=0..floor(n/2)} (k/2)^j * (j+1)^(n-j-1) / (j! * (n-2*j)!).at n=43A362377
- Semiprimes that are the sum of two successive semiprimes and also the sum of three successive semiprimes.at n=44A370162