813918820 has 48 divisors (see below), whose sum is σ = 2008052928. Its totient is φ = 273202560.

The previous prime is 813918803. The next prime is 813918823. The reversal of 813918820 is 28819318.

It is not an unprimeable number, because it can be changed into a prime (813918823) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 139434 + ... + 145153.

It is an arithmetic number, because the mean of its divisors is an integer number (41834436).

Almost surely, 2^813918820 is an apocalyptic number.

It is an amenable number.

813918820 is an abundant number, since it is smaller than the sum of its proper divisors (1194134108).

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

813918820 is a wasteful number, since it uses less digits than its factorization.

813918820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284620 (or 284618 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 40.

The square root of 813918820 is about 28529.2625211378. The cubic root of 813918820 is about 933.6706283745.

The spelling of 813918820 in words is "eight hundred thirteen million, nine hundred eighteen thousand, eight hundred twenty".