9191913691 has 4 divisors (see below), whose sum is σ = 9192108312. Its totient is φ = 9191719072.

The previous prime is 9191913659. The next prime is 9191913733. The reversal of 9191913691 is 1963191919.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 9191913691 - 2⁵ = 9191913659 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9191913191) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23676 + ... + 137638.

It is an arithmetic number, because the mean of its divisors is an integer number (2298027078).

Almost surely, 2^9191913691 is an apocalyptic number.

9191913691 is a deficient number, since it is larger than the sum of its proper divisors (194621).

9191913691 is a wasteful number, since it uses less digits than its factorization.

9191913691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 194620.

The product of its digits is 118098, while the sum is 49.

The square root of 9191913691 is about 95874.4684000908. The cubic root of 9191913691 is about 2094.7650175894.

The spelling of 9191913691 in words is "nine billion, one hundred ninety-one million, nine hundred thirteen thousand, six hundred ninety-one".