20921543892 has 48 divisors (see below), whose sum is σ = 56111428800. Its totient is φ = 6733369440.

The previous prime is 20921543873. The next prime is 20921543893. The reversal of 20921543892 is 29834512902.

20921543892 is a `hidden beast` number, since 2 + 0 + 9 + 21 + 543 + 89 + 2 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20921543893) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3336834 + ... + 3343097.

It is an arithmetic number, because the mean of its divisors is an integer number (1168988100).

Almost surely, 2^20921543892 is an apocalyptic number.

It is an amenable number.

20921543892 is an abundant number, since it is smaller than the sum of its proper divisors (35189884908).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20921543892 is a wasteful number, since it uses less digits than its factorization.

20921543892 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6679973 (or 6679965 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The spelling of 20921543892 in words is "twenty billion, nine hundred twenty-one million, five hundred forty-three thousand, eight hundred ninety-two".