820765868 has 12 divisors (see below), whose sum is σ = 1546828080. Its totient is φ = 378814992.

The previous prime is 820765849. The next prime is 820765871. The reversal of 820765868 is 868567028.

It is a super-2 number, since 2×820765868² = 1347313220147586848, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7891928 + ... + 7892031.

It is an arithmetic number, because the mean of its divisors is an integer number (128902340).

Almost surely, 2^820765868 is an apocalyptic number.

It is an amenable number.

820765868 is a deficient number, since it is larger than the sum of its proper divisors (726062212).

820765868 is a wasteful number, since it uses less digits than its factorization.

820765868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15783976 (or 15783974 counting only the distinct ones).

The product of its (nonzero) digits is 1290240, while the sum is 50.

The square root of 820765868 is about 28649.0116408926. The cubic root of 820765868 is about 936.2814720113.

The spelling of 820765868 in words is "eight hundred twenty million, seven hundred sixty-five thousand, eight hundred sixty-eight".