3205 has 4 divisors (see below), whose sum is σ = 3852. Its totient is φ = 2560.

The previous prime is 3203. The next prime is 3209. The reversal of 3205 is 5023.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2116 + 1089 = 46^2 + 33^2 .

It is not a de Polignac number, because 3205 - 2¹ = 3203 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a plaindrome in base 7 and base 14.

It is a nialpdrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 3191 and 3200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 316 + ... + 325.

It is an arithmetic number, because the mean of its divisors is an integer number (963).

It is an amenable number.

3205 is a deficient number, since it is larger than the sum of its proper divisors (647).

3205 is an equidigital number, since it uses as much as digits as its factorization.

3205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 646.

The product of its (nonzero) digits is 30, while the sum is 10.

The square root of 3205 is about 56.6127194189. The cubic root of 3205 is about 14.7437970662.

Adding to 3205 its reverse (5023), we get a palindrome (8228).

It can be divided in two parts, 320 and 5, that multiplied together give a square (1600 = 40²).

The spelling of 3205 in words is "three thousand, two hundred five".