6645666 has 16 divisors (see below), whose sum is σ = 13869504. Its totient is φ = 2118864.

The previous prime is 6645641. The next prime is 6645677. The reversal of 6645666 is 6665466.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23941 + ... + 24216.

It is an arithmetic number, because the mean of its divisors is an integer number (866844).

Almost surely, 2^6645666 is an apocalyptic number.

6645666 is an abundant number, since it is smaller than the sum of its proper divisors (7223838).

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

6645666 is a wasteful number, since it uses less digits than its factorization.

6645666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48185.

The product of its digits is 155520, while the sum is 39.

The square root of 6645666 is about 2577.9189281279. The cubic root of 6645666 is about 188.0093740610.

The spelling of 6645666 in words is "six million, six hundred forty-five thousand, six hundred sixty-six".