91608520191 has 8 divisors (see below), whose sum is σ = 125123832624. Its totient is φ = 59582777280.

The previous prime is 91608520189. The next prime is 91608520207. The reversal of 91608520191 is 19102580619.

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

It is not a de Polignac number, because 91608520191 - 2¹ = 91608520189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91608520111) 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, 372392236 + ... + 372392481.

It is an arithmetic number, because the mean of its divisors is an integer number (15640479078).

Almost surely, 2^91608520191 is an apocalyptic number.

91608520191 is a deficient number, since it is larger than the sum of its proper divisors (33515312433).

91608520191 is a wasteful number, since it uses less digits than its factorization.

91608520191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 744784761.

The product of its (nonzero) digits is 38880, while the sum is 42.

The spelling of 91608520191 in words is "ninety-one billion, six hundred eight million, five hundred twenty thousand, one hundred ninety-one".