809664580 has 24 divisors (see below), whose sum is σ = 1704470040. Its totient is φ = 323070720.

The previous prime is 809664577. The next prime is 809664589. The reversal of 809664580 is 85466908.

It can be written as a sum of positive squares in 4 ways, for example, as 73410624 + 736253956 = 8568^2 + 27134^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 809664580.

It is not an unprimeable number, because it can be changed into a prime (809664589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41311 + ... + 57670.

It is an arithmetic number, because the mean of its divisors is an integer number (71019585).

Almost surely, 2^809664580 is an apocalyptic number.

It is an amenable number.

809664580 is an abundant number, since it is smaller than the sum of its proper divisors (894805460).

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

809664580 is a wasteful number, since it uses less digits than its factorization.

809664580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99399 (or 99397 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 46.

The square root of 809664580 is about 28454.6056026085. The cubic root of 809664580 is about 932.0410639069.

The spelling of 809664580 in words is "eight hundred nine million, six hundred sixty-four thousand, five hundred eighty".