665742894666 has 8 divisors (see below), whose sum is σ = 1331485789344. Its totient is φ = 221914298220.

The previous prime is 665742894629. The next prime is 665742894697. The reversal of 665742894666 is 666498247566.

It is a sphenic number, since it is the product of 3 distinct primes.

665742894666 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 665742894666.

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, 55478574550 + ... + 55478574561.

It is an arithmetic number, because the mean of its divisors is an integer number (166435723668).

Almost surely, 2^665742894666 is an apocalyptic number.

665742894666 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

665742894666 is a wasteful number, since it uses less digits than its factorization.

665742894666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110957149116.

The product of its digits is 627056640, while the sum is 69.

The spelling of 665742894666 in words is "six hundred sixty-five billion, seven hundred forty-two million, eight hundred ninety-four thousand, six hundred sixty-six".