19391888137 has 2 divisors, whose sum is σ = 19391888138. Its totient is φ = 19391888136.

The previous prime is 19391888123. The next prime is 19391888297. The reversal of 19391888137 is 73188819391.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17496940176 + 1894947961 = 132276^2 + 43531^2 .

It is a cyclic number.

It is not a de Polignac number, because 19391888137 - 2¹¹ = 19391886089 is a prime.

It is not a weakly prime, because it can be changed into another prime (19391888107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9695944068 + 9695944069.

It is an arithmetic number, because the mean of its divisors is an integer number (9695944069).

Almost surely, 2^19391888137 is an apocalyptic number.

It is an amenable number.

19391888137 is a deficient number, since it is larger than the sum of its proper divisors (1).

19391888137 is an equidigital number, since it uses as much as digits as its factorization.

19391888137 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2612736, while the sum is 58.

The spelling of 19391888137 in words is "nineteen billion, three hundred ninety-one million, eight hundred eighty-eight thousand, one hundred thirty-seven".