191385828891 has 20 divisors (see below), whose sum is σ = 289516312800. Its totient is φ = 125975478096.

The previous prime is 191385828871. The next prime is 191385828899. The reversal of 191385828891 is 198828583191.

191385828891 is a `hidden beast` number, since 1 + 91 + 385 + 8 + 2 + 88 + 91 = 666.

It is not a de Polignac number, because 191385828891 - 2¹⁸ = 191385566747 is a prime.

It is a hoax number, since the sum of its digits (63) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (191385828899) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 14947956 + ... + 14960753.

It is an arithmetic number, because the mean of its divisors is an integer number (14475815640).

Almost surely, 2^191385828891 is an apocalyptic number.

191385828891 is a deficient number, since it is larger than the sum of its proper divisors (98130483909).

191385828891 is an equidigital number, since it uses as much as digits as its factorization.

191385828891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29908800 (or 29908791 counting only the distinct ones).

The product of its digits is 9953280, while the sum is 63.

The spelling of 191385828891 in words is "one hundred ninety-one billion, three hundred eighty-five million, eight hundred twenty-eight thousand, eight hundred ninety-one".