1245
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 2016
- Proper Divisor Sum (Aliquot Sum)
- 771
- 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
- 656
- Möbius Function
- -1
- Radical
- 1245
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 3
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
- 88
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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 series-reduced planted trees with n+9 nodes and 4 internal nodes.at n=13A001860
- Expansion of (1+x^3)/((1-x)*(1-x^2)^2*(1-x^3)).at n=33A001973
- Expansion of 1/((1-x)^3*(1-x^2)^2*(1-x^3)).at n=13A002625
- Feynman diagrams of order 2n with vertex skeletons.at n=4A005414
- 12-gonal (or dodecagonal) pyramidal numbers: a(n) = n*(n+1)*(10*n-7)/6.at n=9A007587
- Coordination sequence T2 for Zeolite Code EMT.at n=29A008087
- Numbers n such that phi(n) * sigma(n) + 4 is a perfect square.at n=30A015727
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite RTE = RUB-3 [Si24O48].2R starting with a T3 atom.at n=10A019223
- Values of n for which exp(Pi*sqrt(n)) is very close to an integer.at n=44A019296
- Pseudoprimes to base 82.at n=20A020210
- a(n) = n*(11*n+1)/2.at n=15A022269
- a(n) = n*(25*n - 1)/2.at n=10A022282
- a(n) = [ a(n-1)/a(1) + a(n-3)/a(3) + a(n-5)/a(5) + ... ], for n >= 3.at n=19A022859
- Numbers with exactly 3 4's in base 5 expansion.at n=28A023740
- Every suffix prime and no 0 digits in base 6 (written in base 6).at n=21A024781
- Numbers that are the sum of 3 nonzero squares in exactly 8 ways.at n=38A025328
- Numbers that are the sum of 3 distinct nonzero squares in exactly 8 ways.at n=29A025346
- Index of 6^n within the sequence of the numbers of the form 4^i*6^j.at n=43A025714
- Index of 8^n within the sequence of the numbers of the form 5^i*8^j.at n=43A025729
- Index of 9^n within the sequence of the numbers of the form 7^i*9^j.at n=46A025737