204255781 has 4 divisors (see below), whose sum is σ = 204912864. Its totient is φ = 203598700.

The previous prime is 204255767. The next prime is 204255791. The reversal of 204255781 is 187552402.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 204255781 - 2¹¹ = 204253733 is a prime.

It is a super-2 number, since 2×204255781² = 83440848143839922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204255761) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 328075 + ... + 328696.

It is an arithmetic number, because the mean of its divisors is an integer number (51228216).

Almost surely, 2^204255781 is an apocalyptic number.

It is an amenable number.

204255781 is a deficient number, since it is larger than the sum of its proper divisors (657083).

204255781 is an equidigital number, since it uses as much as digits as its factorization.

204255781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 657082.

The product of its (nonzero) digits is 22400, while the sum is 34.

The square root of 204255781 is about 14291.8081781138. The cubic root of 204255781 is about 588.9224620562.

The spelling of 204255781 in words is "two hundred four million, two hundred fifty-five thousand, seven hundred eighty-one".