99591 has 8 divisors (see below), whose sum is σ = 134640. Its totient is φ = 65472.

The previous prime is 99581. The next prime is 99607. The reversal of 99591 is 19599.

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

It is not a de Polignac number, because 99591 - 2⁵ = 99559 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

99591 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 81 + ... + 453.

It is an arithmetic number, because the mean of its divisors is an integer number (16830).

2⁹⁹⁵⁹¹ is an apocalyptic number.

99591 is a deficient number, since it is larger than the sum of its proper divisors (35049).

99591 is a wasteful number, since it uses less digits than its factorization.

99591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 465.

The product of its digits is 3645, while the sum is 33.

The square root of 99591 is about 315.5804176434. The cubic root of 99591 is about 46.3525215396.

The spelling of 99591 in words is "ninety-nine thousand, five hundred ninety-one".