6660664 has 8 divisors (see below), whose sum is σ = 12488760. Its totient is φ = 3330328.

The previous prime is 6660649. The next prime is 6660677. The reversal of 6660664 is 4660666.

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, 416284 + ... + 416299.

It is an arithmetic number, because the mean of its divisors is an integer number (1561095).

Almost surely, 2^6660664 is an apocalyptic number.

It is an amenable number.

6660664 is a deficient number, since it is larger than the sum of its proper divisors (5828096).

6660664 is a wasteful number, since it uses less digits than its factorization.

6660664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 832589 (or 832585 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 34.

The square root of 6660664 is about 2580.8262242933. The cubic root of 6660664 is about 188.1507015580.

The spelling of 6660664 in words is "six million, six hundred sixty thousand, six hundred sixty-four".