8447491809 has 16 divisors (see below), whose sum is σ = 12946348800. Its totient is φ = 5437465488.

The previous prime is 8447491807. The next prime is 8447491823. The reversal of 8447491809 is 9081947448.

8447491809 is a `hidden beast` number, since 8 + 4 + 474 + 91 + 80 + 9 = 666.

It is not a de Polignac number, because 8447491809 - 2¹ = 8447491807 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (8447491807) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5393529 + ... + 5395094.

It is an arithmetic number, because the mean of its divisors is an integer number (809146800).

Almost surely, 2^8447491809 is an apocalyptic number.

It is an amenable number.

8447491809 is a deficient number, since it is larger than the sum of its proper divisors (4498856991).

8447491809 is a wasteful number, since it uses less digits than its factorization.

8447491809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10788661 (or 10788655 counting only the distinct ones).

The product of its (nonzero) digits is 2322432, while the sum is 54.

The square root of 8447491809 is about 91910.2377812178. The cubic root of 8447491809 is about 2036.6165085453.

The spelling of 8447491809 in words is "eight billion, four hundred forty-seven million, four hundred ninety-one thousand, eight hundred nine".