2856644820 has 84 divisors (see below), whose sum is σ = 8994362580. Its totient is φ = 761768064.

The previous prime is 2856644807. The next prime is 2856644849. The reversal of 2856644820 is 284466582.

2856644820 is a `hidden beast` number, since 2 + 8 + 566 + 4 + 4 + 82 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 828403524 + 2028241296 = 28782^2 + 45036^2 .

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 83385 + ... + 112544.

It is an arithmetic number, because the mean of its divisors is an integer number (107075745).

Almost surely, 2^2856644820 is an apocalyptic number.

2856644820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2856644820 is an abundant number, since it is smaller than the sum of its proper divisors (6137717760).

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

2856644820 is a wasteful number, since it uses less digits than its factorization.

2856644820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195956 (or 195939 counting only the distinct ones).

The product of its (nonzero) digits is 737280, while the sum is 45.

The square root of 2856644820 is about 53447.5894685626. The cubic root of 2856644820 is about 1418.9009580941.

The spelling of 2856644820 in words is "two billion, eight hundred fifty-six million, six hundred forty-four thousand, eight hundred twenty".