204420420421 has 16 divisors (see below), whose sum is σ = 250849923840. Its totient is φ = 162587900160.

The previous prime is 204420420383. The next prime is 204420420437. The reversal of 204420420421 is 124024024402.

It is not a de Polignac number, because 204420420421 - 2¹⁵ = 204420387653 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204420420821) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 12088866 + ... + 12105763.

It is an arithmetic number, because the mean of its divisors is an integer number (15678120240).

Almost surely, 2^204420420421 is an apocalyptic number.

It is an amenable number.

204420420421 is a deficient number, since it is larger than the sum of its proper divisors (46429503419).

204420420421 is a wasteful number, since it uses less digits than its factorization.

204420420421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24194724.

The product of its (nonzero) digits is 4096, while the sum is 25.

Adding to 204420420421 its reverse (124024024402), we get a palindrome (328444444823).

The spelling of 204420420421 in words is "two hundred four billion, four hundred twenty million, four hundred twenty thousand, four hundred twenty-one".