205138065 has 32 divisors (see below), whose sum is σ = 379126656. Its totient is φ = 93608960.

The previous prime is 205138061. The next prime is 205138091. The reversal of 205138065 is 560831502.

It is not a de Polignac number, because 205138065 - 2² = 205138061 is a prime.

It is not an unprimeable number, because it can be changed into a prime (205138061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 33762 + ... + 39371.

It is an arithmetic number, because the mean of its divisors is an integer number (11847708).

Almost surely, 2^205138065 is an apocalyptic number.

It is an amenable number.

205138065 is a deficient number, since it is larger than the sum of its proper divisors (173988591).

205138065 is a wasteful number, since it uses less digits than its factorization.

205138065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73169.

The product of its (nonzero) digits is 7200, while the sum is 30.

The square root of 205138065 is about 14322.6416906938. The cubic root of 205138065 is about 589.7691953682.

Adding to 205138065 its reverse (560831502), we get a palindrome (765969567).

The spelling of 205138065 in words is "two hundred five million, one hundred thirty-eight thousand, sixty-five".