204442721613 has 24 divisors (see below), whose sum is σ = 318070279800. Its totient is φ = 125791810560.

The previous prime is 204442721611. The next prime is 204442721629. The reversal of 204442721613 is 316127244402.

204442721613 is a `hidden beast` number, since 2 + 0 + 4 + 4 + 427 + 216 + 13 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 295083684 + 204147637929 = 17178^2 + 451827^2 .

It is not a de Polignac number, because 204442721613 - 2¹ = 204442721611 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204442721611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 661813 + ... + 920261.

It is an arithmetic number, because the mean of its divisors is an integer number (13252928325).

Almost surely, 2^204442721613 is an apocalyptic number.

It is an amenable number.

204442721613 is a deficient number, since it is larger than the sum of its proper divisors (113627558187).

204442721613 is a wasteful number, since it uses less digits than its factorization.

204442721613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265229 (or 265226 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 36.

The spelling of 204442721613 in words is "two hundred four billion, four hundred forty-two million, seven hundred twenty-one thousand, six hundred thirteen".