811728020 has 12 divisors (see below), whose sum is σ = 1704628884. Its totient is φ = 324691200.

The previous prime is 811727957. The next prime is 811728041. The reversal of 811728020 is 20827118.

It can be written as a sum of positive squares in 2 ways, for example, as 237838084 + 573889936 = 15422^2 + 23956^2 .

It is a congruent number.

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, 20293181 + ... + 20293220.

It is an arithmetic number, because the mean of its divisors is an integer number (142052407).

Almost surely, 2^811728020 is an apocalyptic number.

It is an amenable number.

811728020 is an abundant number, since it is smaller than the sum of its proper divisors (892900864).

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

811728020 is a wasteful number, since it uses less digits than its factorization.

811728020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40586410 (or 40586408 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 29.

The square root of 811728020 is about 28490.8409844287. The cubic root of 811728020 is about 932.8321648946.

The spelling of 811728020 in words is "eight hundred eleven million, seven hundred twenty-eight thousand, twenty".