19930111391 has 2 divisors, whose sum is σ = 19930111392. Its totient is φ = 19930111390.

The previous prime is 19930111373. The next prime is 19930111423. The reversal of 19930111391 is 19311103991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19930111391 - 2²² = 19925917087 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19930111321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9965055695 + 9965055696.

It is an arithmetic number, because the mean of its divisors is an integer number (9965055696).

Almost surely, 2^19930111391 is an apocalyptic number.

19930111391 is a deficient number, since it is larger than the sum of its proper divisors (1).

19930111391 is an equidigital number, since it uses as much as digits as its factorization.

19930111391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6561, while the sum is 38.

The spelling of 19930111391 in words is "nineteen billion, nine hundred thirty million, one hundred eleven thousand, three hundred ninety-one".