205664553 has 6 divisors (see below), whose sum is σ = 297071034. Its totient is φ = 137109696.

The previous prime is 205664513. The next prime is 205664573. The reversal of 205664553 is 355466502.

It is a happy number.

205664553 is a `hidden beast` number, since 2 + 0 + 5 + 6 + 645 + 5 + 3 = 666.

It can be written as a sum of positive squares in only one way, i.e., 163635264 + 42029289 = 12792^2 + 6483^2 .

It is not a de Polignac number, because 205664553 - 2⁸ = 205664297 is a prime.

It is not an unprimeable number, because it can be changed into a prime (205664513) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11425800 + ... + 11425817.

It is an arithmetic number, because the mean of its divisors is an integer number (49511839).

Almost surely, 2^205664553 is an apocalyptic number.

It is an amenable number.

205664553 is a deficient number, since it is larger than the sum of its proper divisors (91406481).

205664553 is a wasteful number, since it uses less digits than its factorization.

205664553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22851623 (or 22851620 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 36.

The square root of 205664553 is about 14341.0094832965. The cubic root of 205664553 is about 590.2733129949.

The spelling of 205664553 in words is "two hundred five million, six hundred sixty-four thousand, five hundred fifty-three".