1686690729 has 16 divisors (see below), whose sum is σ = 2506229440. Its totient is φ = 1121117760.

The previous prime is 1686690703. The next prime is 1686690737. The reversal of 1686690729 is 9270966861.

It is not a de Polignac number, because 1686690729 - 2⁹ = 1686690217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1686695729) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83587 + ... + 101784.

It is an arithmetic number, because the mean of its divisors is an integer number (156639340).

Almost surely, 2^1686690729 is an apocalyptic number.

It is an amenable number.

1686690729 is a deficient number, since it is larger than the sum of its proper divisors (819538711).

1686690729 is a wasteful number, since it uses less digits than its factorization.

1686690729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185717 (or 185711 counting only the distinct ones).

The product of its (nonzero) digits is 1959552, while the sum is 54.

The square root of 1686690729 is about 41069.3404987224. The cubic root of 1686690729 is about 1190.3604418579.

The spelling of 1686690729 in words is "one billion, six hundred eighty-six million, six hundred ninety thousand, seven hundred twenty-nine".