16681008709 has 2 divisors, whose sum is σ = 16681008710. Its totient is φ = 16681008708.

The previous prime is 16681008703. The next prime is 16681008733. The reversal of 16681008709 is 90780018661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13398062500 + 3282946209 = 115750^2 + 57297^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16681008709 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16681008703) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8340504354 + 8340504355.

It is an arithmetic number, because the mean of its divisors is an integer number (8340504355).

Almost surely, 2^16681008709 is an apocalyptic number.

It is an amenable number.

16681008709 is a deficient number, since it is larger than the sum of its proper divisors (1).

16681008709 is an equidigital number, since it uses as much as digits as its factorization.

16681008709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 145152, while the sum is 46.

The spelling of 16681008709 in words is "sixteen billion, six hundred eighty-one million, eight thousand, seven hundred nine".