20571928851 has 4 divisors (see below), whose sum is σ = 27429238472. Its totient is φ = 13714619232.

The previous prime is 20571928841. The next prime is 20571928891. The reversal of 20571928851 is 15882917502.

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

It is not a de Polignac number, because 20571928851 - 2⁶ = 20571928787 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20571928851.

It is not an unprimeable number, because it can be changed into a prime (20571928831) 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 3 ways as a sum of consecutive naturals, for example, 3428654806 + ... + 3428654811.

It is an arithmetic number, because the mean of its divisors is an integer number (6857309618).

Almost surely, 2^20571928851 is an apocalyptic number.

20571928851 is a deficient number, since it is larger than the sum of its proper divisors (6857309621).

20571928851 is an equidigital number, since it uses as much as digits as its factorization.

20571928851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6857309620.

The product of its (nonzero) digits is 403200, while the sum is 48.

The spelling of 20571928851 in words is "twenty billion, five hundred seventy-one million, nine hundred twenty-eight thousand, eight hundred fifty-one".