204721864 has 16 divisors (see below), whose sum is σ = 388713600. Its totient is φ = 101064912.

The previous prime is 204721823. The next prime is 204721883. The reversal of 204721864 is 468127402.

It is a happy number.

204721864 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×204721864² = 83822083199268992, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 161332 + ... + 162595.

It is an arithmetic number, because the mean of its divisors is an integer number (24294600).

Almost surely, 2^204721864 is an apocalyptic number.

It is an amenable number.

204721864 is a deficient number, since it is larger than the sum of its proper divisors (183991736).

204721864 is a wasteful number, since it uses less digits than its factorization.

204721864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324012 (or 324008 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 34.

The square root of 204721864 is about 14308.1048360711. The cubic root of 204721864 is about 589.3700678812.

The spelling of 204721864 in words is "two hundred four million, seven hundred twenty-one thousand, eight hundred sixty-four".