204131340021 has 32 divisors (see below), whose sum is σ = 312622184448. Its totient is φ = 116060616000.

The previous prime is 204131340013. The next prime is 204131340037. The reversal of 204131340021 is 120043131402.

It is not a de Polignac number, because 204131340021 - 2³ = 204131340013 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 204131340021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204131340121) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5161695 + ... + 5201091.

It is an arithmetic number, because the mean of its divisors is an integer number (9769443264).

Almost surely, 2^204131340021 is an apocalyptic number.

204131340021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

204131340021 is a deficient number, since it is larger than the sum of its proper divisors (108490844427).

204131340021 is a wasteful number, since it uses less digits than its factorization.

204131340021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40641.

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 204131340021 its reverse (120043131402), we get a palindrome (324174471423).

The spelling of 204131340021 in words is "two hundred four billion, one hundred thirty-one million, three hundred forty thousand, twenty-one".