17906985666 has 24 divisors (see below), whose sum is σ = 41080732524. Its totient is φ = 5617877760.

The previous prime is 17906985631. The next prime is 17906985671. The reversal of 17906985666 is 66658960971.

It can be written as a sum of positive squares in 2 ways, for example, as 17906454225 + 531441 = 133815^2 + 729^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29259475 + ... + 29260086.

Almost surely, 2^17906985666 is an apocalyptic number.

17906985666 is an abundant number, since it is smaller than the sum of its proper divisors (23173746858).

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

17906985666 is a wasteful number, since it uses less digits than its factorization.

17906985666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58519586 (or 58519583 counting only the distinct ones).

The product of its (nonzero) digits is 29393280, while the sum is 63.

The spelling of 17906985666 in words is "seventeen billion, nine hundred six million, nine hundred eighty-five thousand, six hundred sixty-six".