665370666 has 16 divisors (see below), whose sum is σ = 1478601600. Its totient is φ = 221790204.

The previous prime is 665370659. The next prime is 665370689. The reversal of 665370666 is 666073566.

It is a happy number.

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, 6160786 + ... + 6160893.

It is an arithmetic number, because the mean of its divisors is an integer number (92412600).

Almost surely, 2^665370666 is an apocalyptic number.

665370666 is an abundant number, since it is smaller than the sum of its proper divisors (813230934).

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

665370666 is a wasteful number, since it uses less digits than its factorization.

665370666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12321690 (or 12321684 counting only the distinct ones).

The product of its (nonzero) digits is 816480, while the sum is 45.

The square root of 665370666 is about 25794.7798207312. The cubic root of 665370666 is about 873.0140170870.

The spelling of 665370666 in words is "six hundred sixty-five million, three hundred seventy thousand, six hundred sixty-six".