245
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 11
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 342
- Proper Divisor Sum (Aliquot Sum)
- 97
- 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
- 168
- Möbius Function
- 0
- Radical
- 35
- Omega Function (Ω)
- 3
- 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
- 21
- Smith Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
Names
- German
- zweihundertfünfundvierzig· ordinal: zweihundertfünfundvierzigste
- English
- two hundred forty-five· ordinal: two hundred forty-fifth
- Spanish
- doscientos cuarenta y cinco· ordinal: 245º
- French
- deux cent quarante-cinq· ordinal: deux cent quarante-cinqième
- Italian
- duecentoquarantacinque· ordinal: 245º
- Latin
- ducenti quadraginta quinque· ordinal: 245.
- Portuguese
- duzentos e quarenta e cinco· ordinal: 245º
Appears in sequences
- Number of ways of making change for n cents using coins of 1, 2, 5, 10 cents.at n=44A000008
- Coefficients of the 3rd-order mock theta function f(q).at n=39A000025
- Coefficient of q^(2n-1) in the series expansion of Ramanujan's mock theta function f(q).at n=19A000199
- Numbers m such that Fibonacci(m) ends with m.at n=15A000350
- Expansion of Product_{n>=1} (1 - x^n)^7.at n=34A000730
- Fermat coefficients.at n=3A000972
- Number of ways of making change for n cents using coins of 1, 2, 5, 10, 50, 100 cents.at n=44A001312
- Number of self-dual codes of length 2n over GF(4).at n=9A001646
- Generalized Stirling numbers, [n+6,6]_3.at n=2A001713
- a(1)=2, a(2)=3; for n >= 3, a(n) is smallest number that is uniquely of the form a(j) + a(k) with 1 <= j < k < n.at n=49A001857
- Beatty sequence of (5+sqrt(13))/2.at n=56A001956
- Number of partitions of n into parts 2, 3, 4, 5, 6, 7.at n=30A001996
- Numbers k such that the k-th tetrahedral number is the sum of 2 tetrahedral numbers.at n=10A002311
- 4-dimensional figurate numbers: a(n) = (6*n-2)*binomial(n+2,3)/4.at n=4A002419
- Restricted partitions.at n=12A002574
- Expansion of (1-x)^(-3) * (1-x^2)^(-2).at n=9A002624
- Number of equivalence classes of binary sequences of period n.at n=14A002729
- Numbers k such that (k^2 + 1)/2 is prime.at n=41A002731
- a(n) = Sum_{d|n, d <= 4} d^2 + 4*Sum_{d|n, d>4} d.at n=60A002791
- a(n) = Sum_{d|n, d <= 4} d^2 + 4*Sum_{d|n, d>4} d.at n=31A002791