6447384666 has 24 divisors (see below), whose sum is σ = 14004185364. Its totient is φ = 2143766400.

The previous prime is 6447384631. The next prime is 6447384683. The reversal of 6447384666 is 6664837446.

It can be written as a sum of positive squares in 2 ways, for example, as 5560834041 + 886550625 = 74571^2 + 29775^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 439401 + ... + 453836.

Almost surely, 2^6447384666 is an apocalyptic number.

6447384666 is an abundant number, since it is smaller than the sum of its proper divisors (7556800698).

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

6447384666 is a wasteful number, since it uses less digits than its factorization.

6447384666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 893646 (or 893643 counting only the distinct ones).

The product of its digits is 13934592, while the sum is 54.

The square root of 6447384666 is about 80295.6080118956. The cubic root of 6447384666 is about 1861.2063575441.

The spelling of 6447384666 in words is "six billion, four hundred forty-seven million, three hundred eighty-four thousand, six hundred sixty-six".