19161394191 has 6 divisors (see below), whose sum is σ = 27677569400. Its totient is φ = 12774262788.

The previous prime is 19161394183. The next prime is 19161394201. The reversal of 19161394191 is 19149316191.

19161394191 is a `hidden beast` number, since 19 + 1 + 61 + 394 + 191 = 666.

It is not a de Polignac number, because 19161394191 - 2³ = 19161394183 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19161394391) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1064521891 + ... + 1064521908.

Almost surely, 2^19161394191 is an apocalyptic number.

19161394191 is a deficient number, since it is larger than the sum of its proper divisors (8516175209).

19161394191 is a wasteful number, since it uses less digits than its factorization.

19161394191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2129043805 (or 2129043802 counting only the distinct ones).

The product of its digits is 52488, while the sum is 45.

The spelling of 19161394191 in words is "nineteen billion, one hundred sixty-one million, three hundred ninety-four thousand, one hundred ninety-one".