820769788566 has 128 divisors (see below), whose sum is σ = 2376890127360. Its totient is φ = 203733398016.

The previous prime is 820769788541. The next prime is 820769788589. The reversal of 820769788566 is 665887967028.

820769788566 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 820769788494 and 820769788503.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4829016 + ... + 4996091.

It is an arithmetic number, because the mean of its divisors is an integer number (18569454120).

Almost surely, 2^820769788566 is an apocalyptic number.

820769788566 is an abundant number, since it is smaller than the sum of its proper divisors (1556120338794).

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

820769788566 is a wasteful number, since it uses less digits than its factorization.

820769788566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9825155 (or 9825149 counting only the distinct ones).

The product of its (nonzero) digits is 487710720, while the sum is 72.

The spelling of 820769788566 in words is "eight hundred twenty billion, seven hundred sixty-nine million, seven hundred eighty-eight thousand, five hundred sixty-six".