1686670009 has 2 divisors, whose sum is σ = 1686670010. Its totient is φ = 1686670008.

The previous prime is 1686669989. The next prime is 1686670019. The reversal of 1686670009 is 9000766861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1497690000 + 188980009 = 38700^2 + 13747^2 .

It is an emirp because it is prime and its reverse (9000766861) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1686670009 - 2⁹ = 1686669497 is a prime.

It is not a weakly prime, because it can be changed into another prime (1686670019) by changing a digit.

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 as a sum of consecutive naturals, namely, 843335004 + 843335005.

It is an arithmetic number, because the mean of its divisors is an integer number (843335005).

Almost surely, 2^1686670009 is an apocalyptic number.

It is an amenable number.

1686670009 is a deficient number, since it is larger than the sum of its proper divisors (1).

1686670009 is an equidigital number, since it uses as much as digits as its factorization.

1686670009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 108864, while the sum is 43.

The square root of 1686670009 is about 41069.0882416447. The cubic root of 1686670009 is about 1190.3555675461.

The spelling of 1686670009 in words is "one billion, six hundred eighty-six million, six hundred seventy thousand, nine".