191690400172 has 6 divisors (see below), whose sum is σ = 335458200308. Its totient is φ = 95845200084.

The previous prime is 191690400163. The next prime is 191690400193. The reversal of 191690400172 is 271004096191.

It is an unprimeable number.

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, 23961300018 + ... + 23961300025.

Almost surely, 2^191690400172 is an apocalyptic number.

It is an amenable number.

191690400172 is a deficient number, since it is larger than the sum of its proper divisors (143767800136).

191690400172 is a wasteful number, since it uses less digits than its factorization.

191690400172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47922600047 (or 47922600045 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 40.

The spelling of 191690400172 in words is "one hundred ninety-one billion, six hundred ninety million, four hundred thousand, one hundred seventy-two".