2856638820 has 48 divisors (see below), whose sum is σ = 9141245568. Its totient is φ = 652945920.

The previous prime is 2856638753. The next prime is 2856638833. The reversal of 2856638820 is 288366582.

It is a self number, because there is not a number n which added to its sum of digits gives 2856638820.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3400341 + ... + 3401180.

It is an arithmetic number, because the mean of its divisors is an integer number (190442616).

Almost surely, 2^2856638820 is an apocalyptic number.

2856638820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2856638820 is an abundant number, since it is smaller than the sum of its proper divisors (6284606748).

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

2856638820 is a wasteful number, since it uses less digits than its factorization.

2856638820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6801540 (or 6801538 counting only the distinct ones).

The product of its (nonzero) digits is 1105920, while the sum is 48.

The square root of 2856638820 is about 53447.5333387800. The cubic root of 2856638820 is about 1418.8999646896.

The spelling of 2856638820 in words is "two billion, eight hundred fifty-six million, six hundred thirty-eight thousand, eight hundred twenty".