19688880691 has 2 divisors, whose sum is σ = 19688880692. Its totient is φ = 19688880690.

The previous prime is 19688880689. The next prime is 19688880733. The reversal of 19688880691 is 19608888691.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19688880691 - 2¹ = 19688880689 is a prime.

Together with 19688880689, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (19688881691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9844440345 + 9844440346.

It is an arithmetic number, because the mean of its divisors is an integer number (9844440346).

Almost surely, 2^19688880691 is an apocalyptic number.

19688880691 is a deficient number, since it is larger than the sum of its proper divisors (1).

19688880691 is an equidigital number, since it uses as much as digits as its factorization.

19688880691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11943936, while the sum is 64.

The spelling of 19688880691 in words is "nineteen billion, six hundred eighty-eight million, eight hundred eighty thousand, six hundred ninety-one".