204631431521 has 8 divisors (see below), whose sum is σ = 224292273888. Its totient is φ = 185146920000.

The previous prime is 204631431509. The next prime is 204631431553. The reversal of 204631431521 is 125134136402.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-204631431521 is a prime.

It is a super-3 number, since 3×204631431521³ (a number of 35 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (204631434521) 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, 44080280 + ... + 44084921.

It is an arithmetic number, because the mean of its divisors is an integer number (28036534236).

Almost surely, 2^204631431521 is an apocalyptic number.

It is an amenable number.

204631431521 is a deficient number, since it is larger than the sum of its proper divisors (19660842367).

204631431521 is a wasteful number, since it uses less digits than its factorization.

204631431521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88165423.

The product of its (nonzero) digits is 17280, while the sum is 32.

Adding to 204631431521 its reverse (125134136402), we get a palindrome (329765567923).

The spelling of 204631431521 in words is "two hundred four billion, six hundred thirty-one million, four hundred thirty-one thousand, five hundred twenty-one".