205

Number
$205$ (two hundred and five) is:


 * $5 \times 41$


 * The $13$th integer after $7, 13, 19, 35, 38, 41, 57, 65, 70, 125, 130, 190$ the decimal representation of whose square can be split into two parts which are each themselves square:
 * $205^2 = 42 \, 025; 4 = 2^2, 2025 = 45^2$


 * The $40$th lucky number:
 * $1, 3, 7, 9, 13, 15, 21, \ldots, 163, 169, 171, 189, 193, 195, 201, 205, \ldots$


 * The $10$th positive integer after $50, 65, 85, 125, 130, 145, 170, 185, 200$ which can be expressed as the sum of two square numbers in two or more different ways:
 * $205 = 14^2 + 3^2 = 13^2 + 6^2$


 * The $4$th positive integer after $200, 202, 204$ that cannot be made into a prime number by changing just $1$ digit

Also see

 * Integer Greater than 205 is Sum of Distinct Primes of form 6 n + 1