1577
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 1680
- Proper Divisor Sum (Aliquot Sum)
- 103
- 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
- 1476
- Möbius Function
- 1
- Radical
- 1577
- 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
- 91
- 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
- Generalized divisor function. Number of partitions of n with exactly three part sizes.at n=27A002134
- Arrays of dumbbells.at n=6A002941
- Number of points on surface of tricapped prism: a(n) = 7*n^2 + 2 for n > 0, a(0)=1.at n=15A005919
- Coordination sequence T1 for Zeolite Code AEI.at n=30A008001
- Coordination sequence T2 for Zeolite Code AEI.at n=30A008002
- Coordination sequence T1 for Zeolite Code BRE.at n=26A008058
- Coordination sequence T3 for Zeolite Code MTT.at n=24A008191
- Coordination sequence T6 for Zeolite Code CON.at n=28A009873
- (n-th Fibonacci number that is not 1) - (n-th number that is 1 or not a Fibonacci number).at n=14A014242
- a(n) = smallest k >= n such that k | (2^k + n).at n=22A015948
- Nine iterations of Reverse and Add are needed to reach a palindrome.at n=2A015990
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite BEA = Beta Na7[Al7Si57O128] starting with a T7 atom.at n=10A019073
- Coordination sequence T3 for Zeolite Code SAO.at n=31A019573
- Numbers k such that the continued fraction for sqrt(k) has period 26.at n=33A020365
- Dying rabbits: a(n) = a(n-1) + a(n-2) - a(n-12).at n=17A023442
- Number of 4's in all partitions of n.at n=25A024788
- a(n) = sum of the numbers between the two n's in A026242.at n=37A026271
- Number of partitions of n into an even number of parts, the least being 6; also, a(n+6) = number of partitions of n into an odd number of parts, each >=6.at n=68A027198
- Positions of record values in A030787.at n=38A030792
- Numbers k such that 255*2^k+1 is prime.at n=24A032504