91001599 has 6 divisors (see below), whose sum is σ = 98540376. Its totient is φ = 84001320.

The previous prime is 91001567. The next prime is 91001641. The reversal of 91001599 is 99510019.

It is not a de Polignac number, because 91001599 - 2⁵ = 91001567 is a prime.

It is a Duffinian number.

91001599 is a modest number, since divided by 1599 gives 910 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91001539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 269067 + ... + 269404.

It is an arithmetic number, because the mean of its divisors is an integer number (16423396).

Almost surely, 2^91001599 is an apocalyptic number.

91001599 is a deficient number, since it is larger than the sum of its proper divisors (7538777).

91001599 is a wasteful number, since it uses less digits than its factorization.

91001599 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 538497 (or 538484 counting only the distinct ones).

The product of its (nonzero) digits is 3645, while the sum is 34.

The square root of 91001599 is about 9539.4758241740. The cubic root of 91001599 is about 449.7967790207.

The spelling of 91001599 in words is "ninety-one million, one thousand, five hundred ninety-nine".