665908185616 has 10 divisors (see below), whose sum is σ = 1290197109662. Its totient is φ = 332954092800.

The previous prime is 665908185599. The next prime is 665908185689. The reversal of 665908185616 is 616581809566.

It can be written as a sum of positive squares in only one way, i.e., 663253875216 + 2654310400 = 814404^2 + 51520^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20809630785 + ... + 20809630816.

Almost surely, 2^665908185616 is an apocalyptic number.

It is an amenable number.

665908185616 is a deficient number, since it is larger than the sum of its proper divisors (624288924046).

665908185616 is a wasteful number, since it uses less digits than its factorization.

665908185616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41619261609 (or 41619261603 counting only the distinct ones).

The product of its (nonzero) digits is 18662400, while the sum is 61.

The spelling of 665908185616 in words is "six hundred sixty-five billion, nine hundred eight million, one hundred eighty-five thousand, six hundred sixteen".