19906388113 has 2 divisors, whose sum is σ = 19906388114. Its totient is φ = 19906388112.

The previous prime is 19906388087. The next prime is 19906388123. The reversal of 19906388113 is 31188360991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18287693824 + 1618694289 = 135232^2 + 40233^2 .

It is a cyclic number.

It is not a de Polignac number, because 19906388113 - 2²¹ = 19904290961 is a prime.

It is not a weakly prime, because it can be changed into another prime (19906388123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9953194056 + 9953194057.

It is an arithmetic number, because the mean of its divisors is an integer number (9953194057).

Almost surely, 2^19906388113 is an apocalyptic number.

It is an amenable number.

19906388113 is a deficient number, since it is larger than the sum of its proper divisors (1).

19906388113 is an equidigital number, since it uses as much as digits as its factorization.

19906388113 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 279936, while the sum is 49.

The spelling of 19906388113 in words is "nineteen billion, nine hundred six million, three hundred eighty-eight thousand, one hundred thirteen".