20811820812 has 24 divisors (see below), whose sum is σ = 48563345712. Its totient is φ = 6936926400.

The previous prime is 20811820789. The next prime is 20811820847. The reversal of 20811820812 is 21802811802.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 346362 + ... + 401982.

It is an arithmetic number, because the mean of its divisors is an integer number (2023472738).

Almost surely, 2^20811820812 is an apocalyptic number.

It is an amenable number.

20811820812 is an abundant number, since it is smaller than the sum of its proper divisors (27751524900).

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

20811820812 is a wasteful number, since it uses less digits than its factorization.

20811820812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86809 (or 86807 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 33.

The spelling of 20811820812 in words is "twenty billion, eight hundred eleven million, eight hundred twenty thousand, eight hundred twelve".