813905920 has 96 divisors (see below), whose sum is σ = 1986435360. Its totient is φ = 319979520.

The previous prime is 813905861. The next prime is 813905921. The reversal of 813905920 is 29509318.

It is a super-2 number, since 2×813905920² = 1324885693222092800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 813905920.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (813905921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 623989 + ... + 625291.

It is an arithmetic number, because the mean of its divisors is an integer number (20692035).

Almost surely, 2^813905920 is an apocalyptic number.

813905920 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 813905920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (993217680).

813905920 is an abundant number, since it is smaller than the sum of its proper divisors (1172529440).

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

813905920 is a wasteful number, since it uses less digits than its factorization.

813905920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1391 (or 1371 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 37.

The square root of 813905920 is about 28529.0364365851. The cubic root of 813905920 is about 933.6656956898.

The spelling of 813905920 in words is "eight hundred thirteen million, nine hundred five thousand, nine hundred twenty".