1816564806 has 160 divisors (see below), whose sum is σ = 4983264000. Its totient is φ = 483029568.

The previous prime is 1816564781. The next prime is 1816564823. The reversal of 1816564806 is 6084656181.

1816564806 is a `hidden beast` number, since 1 + 8 + 1 + 6 + 564 + 80 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1270500 + ... + 1271928.

It is an arithmetic number, because the mean of its divisors is an integer number (31145400).

Almost surely, 2^1816564806 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1816564806, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2491632000).

1816564806 is an abundant number, since it is smaller than the sum of its proper divisors (3166699194).

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

1816564806 is a wasteful number, since it uses less digits than its factorization.

1816564806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1528 (or 1519 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The square root of 1816564806 is about 42621.1779048867. The cubic root of 1816564806 is about 1220.1605105485.

The spelling of 1816564806 in words is "one billion, eight hundred sixteen million, five hundred sixty-four thousand, eight hundred six".