1681986685 has 16 divisors (see below), whose sum is σ = 2193154560. Its totient is φ = 1233645120.

The previous prime is 1681986679. The next prime is 1681986707. The reversal of 1681986685 is 5866891861.

It is not a de Polignac number, because 1681986685 - 2⁵ = 1681986653 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 282622 + ... + 288511.

It is an arithmetic number, because the mean of its divisors is an integer number (137072160).

Almost surely, 2^1681986685 is an apocalyptic number.

It is an amenable number.

1681986685 is a deficient number, since it is larger than the sum of its proper divisors (511167875).

1681986685 is a wasteful number, since it uses less digits than its factorization.

1681986685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 571188.

The product of its digits is 4976640, while the sum is 58.

The square root of 1681986685 is about 41012.0309787262. The cubic root of 1681986685 is about 1189.2528051893.

The spelling of 1681986685 in words is "one billion, six hundred eighty-one million, nine hundred eighty-six thousand, six hundred eighty-five".