91799391 has 8 divisors (see below), whose sum is σ = 122666544. Its totient is φ = 61065920.

The previous prime is 91799387. The next prime is 91799419. The reversal of 91799391 is 19399719.

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

It is a cyclic number.

It is not a de Polignac number, because 91799391 - 2² = 91799387 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 91799391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91799321) 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 7 ways as a sum of consecutive naturals, for example, 31806 + ... + 34571.

It is an arithmetic number, because the mean of its divisors is an integer number (15333318).

Almost surely, 2^91799391 is an apocalyptic number.

91799391 is a deficient number, since it is larger than the sum of its proper divisors (30867153).

91799391 is a wasteful number, since it uses less digits than its factorization.

91799391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66841.

The product of its digits is 137781, while the sum is 48.

The square root of 91799391 is about 9581.1998726673. The cubic root of 91799391 is about 451.1073813103.

The spelling of 91799391 in words is "ninety-one million, seven hundred ninety-nine thousand, three hundred ninety-one".