204643135021 has 8 divisors (see below), whose sum is σ = 220388706720. Its totient is φ = 188898105072.

The previous prime is 204643135013. The next prime is 204643135027. The reversal of 204643135021 is 120531346402.

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

It is a cyclic number.

It is not a de Polignac number, because 204643135021 - 2³ = 204643135013 is a prime.

It is a super-2 number, since 2×204643135021² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204643135027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1004550 + ... + 1190968.

It is an arithmetic number, because the mean of its divisors is an integer number (27548588340).

Almost surely, 2^204643135021 is an apocalyptic number.

It is an amenable number.

204643135021 is a deficient number, since it is larger than the sum of its proper divisors (15745571699).

204643135021 is a wasteful number, since it uses less digits than its factorization.

204643135021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270875.

The product of its (nonzero) digits is 17280, while the sum is 31.

The spelling of 204643135021 in words is "two hundred four billion, six hundred forty-three million, one hundred thirty-five thousand, twenty-one".