665044971 has 16 divisors (see below), whose sum is σ = 907490304. Its totient is φ = 433021184.

The previous prime is 665044967. The next prime is 665044979. The reversal of 665044971 is 179440566.

It is a cyclic number.

It is not a de Polignac number, because 665044971 - 2² = 665044967 is a prime.

It is not an unprimeable number, because it can be changed into a prime (665044979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 66235 + ... + 75611.

It is an arithmetic number, because the mean of its divisors is an integer number (56718144).

Almost surely, 2^665044971 is an apocalyptic number.

665044971 is a deficient number, since it is larger than the sum of its proper divisors (242445333).

665044971 is a wasteful number, since it uses less digits than its factorization.

665044971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9930.

The product of its (nonzero) digits is 181440, while the sum is 42.

The square root of 665044971 is about 25788.4658520045. The cubic root of 665044971 is about 872.8715487751.

The spelling of 665044971 in words is "six hundred sixty-five million, forty-four thousand, nine hundred seventy-one".