1993663686 has 24 divisors (see below), whose sum is σ = 4638320280. Its totient is φ = 569618112.

The previous prime is 1993663619. The next prime is 1993663699. The reversal of 1993663686 is 6863663991.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors.

It is a congruent number.

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, 3390291 + ... + 3390878.

It is an arithmetic number, because the mean of its divisors is an integer number (193263345).

Almost surely, 2^1993663686 is an apocalyptic number.

1993663686 is an abundant number, since it is smaller than the sum of its proper divisors (2644656594).

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

1993663686 is a wasteful number, since it uses less digits than its factorization.

1993663686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6781188 (or 6781181 counting only the distinct ones).

The product of its digits is 7558272, while the sum is 57.

The square root of 1993663686 is about 44650.4612070245. The cubic root of 1993663686 is about 1258.5890997294.

The spelling of 1993663686 in words is "one billion, nine hundred ninety-three million, six hundred sixty-three thousand, six hundred eighty-six".