6444880664 has 8 divisors (see below), whose sum is σ = 12084151260. Its totient is φ = 3222440328.

The previous prime is 6444880643. The next prime is 6444880681. The reversal of 6444880664 is 4660884446.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 402805034 + ... + 402805049.

Almost surely, 2^6444880664 is an apocalyptic number.

It is an amenable number.

6444880664 is a deficient number, since it is larger than the sum of its proper divisors (5639270596).

6444880664 is a wasteful number, since it uses less digits than its factorization.

6444880664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 805610089 (or 805610085 counting only the distinct ones).

The product of its (nonzero) digits is 3538944, while the sum is 50.

The square root of 6444880664 is about 80280.0141006465. The cubic root of 6444880664 is about 1860.9653777697.

The spelling of 6444880664 in words is "six billion, four hundred forty-four million, eight hundred eighty thousand, six hundred sixty-four".