204225021 has 48 divisors (see below), whose sum is σ = 396090240. Its totient is φ = 97925760.

The previous prime is 204224987. The next prime is 204225037. The reversal of 204225021 is 120522402.

It is not a de Polignac number, because 204225021 - 2²⁵ = 170670589 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 204224985 and 204225003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204225071) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2326 + ... + 20343.

It is an arithmetic number, because the mean of its divisors is an integer number (8251880).

Almost surely, 2^204225021 is an apocalyptic number.

204225021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

204225021 is a deficient number, since it is larger than the sum of its proper divisors (191865219).

204225021 is a wasteful number, since it uses less digits than its factorization.

204225021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22706 (or 22703 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 204225021 is about 14290.7319966473. The cubic root of 204225021 is about 588.8928975493.

Adding to 204225021 its reverse (120522402), we get a palindrome (324747423).

The spelling of 204225021 in words is "two hundred four million, two hundred twenty-five thousand, twenty-one".