2545
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
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 3060
- Proper Divisor Sum (Aliquot Sum)
- 515
- 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
- 2032
- Möbius Function
- 1
- Radical
- 2545
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 40
- 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
- Number of partitions into non-integral powers.at n=24A000148
- Numbers m such that Fibonacci(m) ends with m.at n=47A000350
- Expansion of 1/((1-x)^2*(1-x^2)*(1-x^5)).at n=49A001304
- Coordination sequence for Paracelsian.at n=34A008260
- Coordination sequence T5 for Zeolite Code VNI.at n=31A009911
- Coordination sequence for sigma-CrFe, Position Xd.at n=13A009959
- Number of (unordered) triples of integers from [1,n] with no common factors between pairs.at n=36A015617
- Numbers k such that the continued fraction for sqrt(k) has period 15.at n=14A020354
- Pisot sequence P(5,11), a(0)=5, a(1)=11, a(n+1) is the nearest integer to a(n)^2/a(n-1).at n=8A021008
- Sequence satisfies T^2(a)=a, where T is defined below.at n=40A027588
- Lucky numbers with size of gaps equal to 12 (lower terms).at n=32A031894
- Lucky numbers with size of gaps equal to 18 (upper terms).at n=16A031901
- Numbers with exactly five distinct base-7 digits.at n=10A031984
- Quotient of 'base-24' division described in A032579.at n=57A032580
- a(0)=2; a(n) is the smallest k > a(n-1) such that the fractional part of k^(1/9) starts with n.at n=39A034074
- Denominators of continued fraction convergents to sqrt(498).at n=4A041951
- Numbers n such that string 3,7 occurs in the base 9 representation of n but not of n-1.at n=35A044285
- Numbers n such that string 4,5 occurs in the base 10 representation of n but not of n-1.at n=28A044377
- Numbers n such that string 3,7 occurs in the base 9 representation of n but not of n+1.at n=35A044666
- Numbers n such that string 4,5 occurs in the base 10 representation of n but not of n+1.at n=28A044758