9191010091 has 4 divisors (see below), whose sum is σ = 9192030184. Its totient is φ = 9189990000.

The previous prime is 9191010083. The next prime is 9191010119. The reversal of 9191010091 is 1900101919.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1900101919 = 2267 ⋅838157.

It is a cyclic number.

It is not a de Polignac number, because 9191010091 - 2³ = 9191010083 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9191010991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 496410 + ... + 514591.

It is an arithmetic number, because the mean of its divisors is an integer number (2298007546).

Almost surely, 2^9191010091 is an apocalyptic number.

9191010091 is a deficient number, since it is larger than the sum of its proper divisors (1020093).

9191010091 is a wasteful number, since it uses less digits than its factorization.

9191010091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1020092.

The product of its (nonzero) digits is 729, while the sum is 31.

The square root of 9191010091 is about 95869.7558722249. The cubic root of 9191010091 is about 2094.6963742230.

The spelling of 9191010091 in words is "nine billion, one hundred ninety-one million, ten thousand, ninety-one".