205601 has 4 divisors (see below), whose sum is σ = 224304. Its totient is φ = 186900.

The previous prime is 205589. The next prime is 205603. The reversal of 205601 is 106502.

205601 is an esthetic number in base 16, because in such base its adjacent digits differ by 1.

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 a cyclic number.

It is not a de Polignac number, because 205601 - 2⁶ = 205537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9335 + ... + 9356.

It is an arithmetic number, because the mean of its divisors is an integer number (56076).

2²⁰⁵⁶⁰¹ is an apocalyptic number.

It is an amenable number.

205601 is a deficient number, since it is larger than the sum of its proper divisors (18703).

205601 is a wasteful number, since it uses less digits than its factorization.

205601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18702.

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 205601 is about 453.4324646516. The cubic root of 205601 is about 59.0212506042.

Subtracting from 205601 its reverse (106502), we obtain a palindrome (99099).

The spelling of 205601 in words is "two hundred five thousand, six hundred one".