191091911091 has 8 divisors (see below), whose sum is σ = 257126730960. Its totient is φ = 126225849312.

The previous prime is 191091911083. The next prime is 191091911111. The reversal of 191091911091 is 190119190191.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 191091911091 - 2³ = 191091911083 is a prime.

It is a super-2 number, since 2×191091911091² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (191091911051) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 292189140 + ... + 292189793.

It is an arithmetic number, because the mean of its divisors is an integer number (32140841370).

Almost surely, 2^191091911091 is an apocalyptic number.

191091911091 is a deficient number, since it is larger than the sum of its proper divisors (66034819869).

191091911091 is a wasteful number, since it uses less digits than its factorization.

191091911091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 584379045.

The product of its (nonzero) digits is 6561, while the sum is 42.

The spelling of 191091911091 in words is "one hundred ninety-one billion, ninety-one million, nine hundred eleven thousand, ninety-one".