819918220 has 48 divisors (see below), whose sum is σ = 1880879616. Its totient is φ = 297752000.

The previous prime is 819918179. The next prime is 819918227. The reversal of 819918220 is 22819918.

It is not an unprimeable number, because it can be changed into a prime (819918227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 198375 + ... + 202465.

It is an arithmetic number, because the mean of its divisors is an integer number (39184992).

Almost surely, 2^819918220 is an apocalyptic number.

It is an amenable number.

819918220 is an abundant number, since it is smaller than the sum of its proper divisors (1060961396).

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

819918220 is a wasteful number, since it uses less digits than its factorization.

819918220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5022 (or 5020 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 40.

The square root of 819918220 is about 28634.2141502085. The cubic root of 819918220 is about 935.9590453140.

The spelling of 819918220 in words is "eight hundred nineteen million, nine hundred eighteen thousand, two hundred twenty".