1686330409 has 4 divisors (see below), whose sum is σ = 1686425940. Its totient is φ = 1686234880.

The previous prime is 1686330407. The next prime is 1686330439. The reversal of 1686330409 is 9040336861.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 9040336861 = 41 ⋅220496021.

It can be written as a sum of positive squares in 2 ways, for example, as 855738009 + 830592400 = 29253^2 + 28820^2 .

It is a cyclic number.

It is not a de Polignac number, because 1686330409 - 2¹ = 1686330407 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1686330407) 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 in 3 ways as a sum of consecutive naturals, for example, 12712 + ... + 59449.

It is an arithmetic number, because the mean of its divisors is an integer number (421606485).

Almost surely, 2^1686330409 is an apocalyptic number.

It is an amenable number.

1686330409 is a deficient number, since it is larger than the sum of its proper divisors (95531).

1686330409 is an equidigital number, since it uses as much as digits as its factorization.

1686330409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95530.

The product of its (nonzero) digits is 93312, while the sum is 40.

The square root of 1686330409 is about 41064.9535370491. The cubic root of 1686330409 is about 1190.2756720751.

The spelling of 1686330409 in words is "one billion, six hundred eighty-six million, three hundred thirty thousand, four hundred nine".