6665251664 has 80 divisors (see below), whose sum is σ = 13343253120. Its totient is φ = 3224309760.

The previous prime is 6665251657. The next prime is 6665251667. The reversal of 6665251664 is 4661525666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6665251667) 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, 17586227 + ... + 17586605.

It is an arithmetic number, because the mean of its divisors is an integer number (166790664).

Almost surely, 2^6665251664 is an apocalyptic number.

It is an amenable number.

6665251664 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

6665251664 is a wasteful number, since it uses less digits than its factorization.

6665251664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 708 (or 702 counting only the distinct ones).

The product of its digits is 1555200, while the sum is 47.

The square root of 6665251664 is about 81640.9925466368. The cubic root of 6665251664 is about 1881.9388914911.

The spelling of 6665251664 in words is "six billion, six hundred sixty-five million, two hundred fifty-one thousand, six hundred sixty-four".