6491607664 has 20 divisors (see below), whose sum is σ = 12845097504. Its totient is φ = 3176743808.

The previous prime is 6491607649. The next prime is 6491607737. The reversal of 6491607664 is 4667061946.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4315477 + ... + 4316980.

Almost surely, 2^6491607664 is an apocalyptic number.

It is an amenable number.

6491607664 is a deficient number, since it is larger than the sum of its proper divisors (6353489840).

6491607664 is a wasteful number, since it uses less digits than its factorization.

6491607664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8632512 (or 8632506 counting only the distinct ones).

The product of its (nonzero) digits is 1306368, while the sum is 49.

The square root of 6491607664 is about 80570.5136138526. The cubic root of 6491607664 is about 1865.4520404921.

The spelling of 6491607664 in words is "six billion, four hundred ninety-one million, six hundred seven thousand, six hundred sixty-four".