204425991 has 72 divisors (see below), whose sum is σ = 387540720. Its totient is φ = 106112160.

The previous prime is 204425957. The next prime is 204425993. The reversal of 204425991 is 199524402.

204425991 is a `hidden beast` number, since 20 + 4 + 42 + 599 + 1 = 666.

204425991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 204425991 - 2⁹ = 204425479 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204425993) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 159445 + ... + 160721.

It is an arithmetic number, because the mean of its divisors is an integer number (5382510).

Almost surely, 2^204425991 is an apocalyptic number.

204425991 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

204425991 is a deficient number, since it is larger than the sum of its proper divisors (183114729).

204425991 is a wasteful number, since it uses less digits than its factorization.

204425991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1322 (or 1298 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 204425991 is about 14297.7617479101. The cubic root of 204425991 is about 589.0860031820.

The spelling of 204425991 in words is "two hundred four million, four hundred twenty-five thousand, nine hundred ninety-one".