665518018 has 16 divisors (see below), whose sum is σ = 1136379456. Its totient is φ = 289355440.

The previous prime is 665517953. The next prime is 665518019. The reversal of 665518018 is 810815566.

It is not an unprimeable number, because it can be changed into a prime (665518019) 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 7 ways as a sum of consecutive naturals, for example, 657121 + ... + 658132.

It is an arithmetic number, because the mean of its divisors is an integer number (71023716).

Almost surely, 2^665518018 is an apocalyptic number.

665518018 is a deficient number, since it is larger than the sum of its proper divisors (470861438).

665518018 is a wasteful number, since it uses less digits than its factorization.

665518018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1315289.

The product of its (nonzero) digits is 57600, while the sum is 40.

The square root of 665518018 is about 25797.6358994385. The cubic root of 665518018 is about 873.0784577930.

The spelling of 665518018 in words is "six hundred sixty-five million, five hundred eighteen thousand, eighteen".