20537388385 has 4 divisors (see below), whose sum is σ = 24644866068. Its totient is φ = 16429910704.

The previous prime is 20537388349. The next prime is 20537388449. The reversal of 20537388385 is 58388373502.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5135585569 + 15401802816 = 71663^2 + 124104^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20537388385 is a prime.

It is a Duffinian number.

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 3 ways as a sum of consecutive naturals, for example, 2053738834 + ... + 2053738843.

It is an arithmetic number, because the mean of its divisors is an integer number (6161216517).

Almost surely, 2^20537388385 is an apocalyptic number.

It is an amenable number.

20537388385 is a deficient number, since it is larger than the sum of its proper divisors (4107477683).

20537388385 is an equidigital number, since it uses as much as digits as its factorization.

20537388385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4107477682.

The product of its (nonzero) digits is 4838400, while the sum is 52.

The spelling of 20537388385 in words is "twenty billion, five hundred thirty-seven million, three hundred eighty-eight thousand, three hundred eighty-five".