15961
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 17424
- Proper Divisor Sum (Aliquot Sum)
- 1463
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 14500
- Möbius Function
- 1
- Radical
- 15961
- 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
- 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
- a(n) = n*(3*n^2 - 1)/2.at n=22A004188
- a(n) = 8^n - 7^n.at n=5A016177
- Positive numbers k such that k = x^5 + y^5 has a solution in nonzero integers x, y.at n=39A020896
- a(n) = (n+1)^5 - n^5.at n=7A022521
- Number of partitions of n into parts not of the form 21k, 21k+9 or 21k-9. Also number of partitions with at most 8 parts of size 1 and differences between parts at distance 9 are greater than 1.at n=36A035987
- pi(n) associated with A049529.at n=7A049530
- Number of positive integers <= 2^n of form 2 x^2 + 9 y^2.at n=17A054159
- Number of symmetric types of (3,2n)-hypergraphs under action of complementing group C(3,2).at n=36A055780
- a(n) = Catalan(n) - Motzkin(n-1).at n=9A058987
- a(n) = 8^n mod 7^n.at n=5A138973
- Numbers expressible as the difference of two nonnegative fifth powers.at n=25A152045
- Number of "ON" cubic cells at n-th stage in simple 3-dimensional cellular automaton: a(n) = A160428(n)/8.at n=31A161342
- Totally multiplicative sequence with a(p) = a(p-1) + 10 for prime p.at n=21A166707
- a(n) = Sum_{k=0..[n/2]} C(n-k,k)^4*n/(n-k), n>=1.at n=6A166899
- Difference of two positive 5th powers.at n=19A181124
- Monotonic ordering of nonnegative differences 2^i-7^j, for 40>=i>=0, j>=0.at n=40A192118
- Nonprime numbers with all divisors starting and ending with digit 1.at n=28A208261
- Sizes of logical groups of the same integer in A229895.at n=32A229896
- Odd integers k such that for every m >= 1 the numbers k*4^m - 1 have at least three prime factors, not necessarily distinct, and k*4^m - 1 has at least two-element covering set.at n=24A233552
- Indices of primes in A214831.at n=26A244930