204065221665 has 8 divisors (see below), whose sum is σ = 326504354688. Its totient is φ = 108834784880.

The previous prime is 204065221603. The next prime is 204065221709. The reversal of 204065221665 is 566122560402.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 204065221665 - 2¹⁰ = 204065220641 is a prime.

It is a super-2 number, since 2×204065221665² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6802174041 + ... + 6802174070.

It is an arithmetic number, because the mean of its divisors is an integer number (40813044336).

Almost surely, 2^204065221665 is an apocalyptic number.

It is an amenable number.

204065221665 is a deficient number, since it is larger than the sum of its proper divisors (122439133023).

204065221665 is a wasteful number, since it uses less digits than its factorization.

204065221665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13604348119.

The product of its (nonzero) digits is 172800, while the sum is 39.

The spelling of 204065221665 in words is "two hundred four billion, sixty-five million, two hundred twenty-one thousand, six hundred sixty-five".