205613 has 4 divisors (see below), whose sum is σ = 207360. Its totient is φ = 203868.

The previous prime is 205607. The next prime is 205619. The reversal of 205613 is 316502.

205613 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (205607) and next prime (205619).

It is a cyclic number.

It is not a de Polignac number, because 205613 - 2⁶ = 205549 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 205591 and 205600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205619) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 683 + ... + 936.

It is an arithmetic number, because the mean of its divisors is an integer number (51840).

2²⁰⁵⁶¹³ is an apocalyptic number.

It is an amenable number.

205613 is a deficient number, since it is larger than the sum of its proper divisors (1747).

205613 is a wasteful number, since it uses less digits than its factorization.

205613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1746.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 205613 is about 453.4456968591. The cubic root of 205613 is about 59.0223988496.

Subtracting 205613 from its reverse (316502), we obtain a square (110889 = 333²).

It can be divided in two parts, 205 and 613, that added together give a palindrome (818).

The spelling of 205613 in words is "two hundred five thousand, six hundred thirteen".