813571920 has 240 divisors, whose sum is σ = 3138370560. Its totient is φ = 185020416.

The previous prime is 813571919. The next prime is 813571931. The reversal of 813571920 is 29175318.

813571920 is a `hidden beast` number, since 81 + 3 + 571 + 9 + 2 + 0 = 666.

813571920 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1698241 + ... + 1698719.

It is an arithmetic number, because the mean of its divisors is an integer number (13076544).

Almost surely, 2^813571920 is an apocalyptic number.

813571920 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 813571920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1569185280).

813571920 is an abundant number, since it is smaller than the sum of its proper divisors (2324798640).

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

813571920 is a wasteful number, since it uses less digits than its factorization.

813571920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 842 (or 833 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

The square root of 813571920 is about 28523.1821506647. The cubic root of 813571920 is about 933.5379630689.

The spelling of 813571920 in words is "eight hundred thirteen million, five hundred seventy-one thousand, nine hundred twenty".