204553111221 has 12 divisors (see below), whose sum is σ = 296409588748. Its totient is φ = 135933056064.

The previous prime is 204553111207. The next prime is 204553111223. The reversal of 204553111221 is 122111355402.

It is a happy number.

204553111221 is a `hidden beast` number, since 2 + 0 + 4 + 5 + 531 + 1 + 122 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 37937300625 + 166615810596 = 194775^2 + 408186^2 .

It is not a de Polignac number, because 204553111221 - 2⁷ = 204553111093 is a prime.

It is a super-2 number, since 2×204553111221² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204553111223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36304090 + ... + 36309723.

Almost surely, 2^204553111221 is an apocalyptic number.

It is an amenable number.

204553111221 is a deficient number, since it is larger than the sum of its proper divisors (91856477527).

204553111221 is a wasteful number, since it uses less digits than its factorization.

204553111221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72614132 (or 72614129 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

Adding to 204553111221 its reverse (122111355402), we get a palindrome (326664466623).

The spelling of 204553111221 in words is "two hundred four billion, five hundred fifty-three million, one hundred eleven thousand, two hundred twenty-one".