205724961 has 16 divisors (see below), whose sum is σ = 328222720. Its totient is φ = 126599760.

The previous prime is 205724957. The next prime is 205724983. The reversal of 205724961 is 169427502.

205724961 is a `hidden beast` number, since 20 + 572 + 4 + 9 + 61 = 666.

It is not a de Polignac number, because 205724961 - 2² = 205724957 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (205724261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 292705 + ... + 293406.

It is an arithmetic number, because the mean of its divisors is an integer number (20513920).

Almost surely, 2^205724961 is an apocalyptic number.

It is an amenable number.

205724961 is a deficient number, since it is larger than the sum of its proper divisors (122497759).

205724961 is a wasteful number, since it uses less digits than its factorization.

205724961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 586133 (or 586127 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 205724961 is about 14343.1154565527. The cubic root of 205724961 is about 590.3310992286.

The spelling of 205724961 in words is "two hundred five million, seven hundred twenty-four thousand, nine hundred sixty-one".