91660599 has 16 divisors (see below), whose sum is σ = 136867840. Its totient is φ = 60623640.

The previous prime is 91660567. The next prime is 91660643. The reversal of 91660599 is 99506619.

It is not a de Polignac number, because 91660599 - 2⁵ = 91660567 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91660519) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9937 + ... + 16794.

It is an arithmetic number, because the mean of its divisors is an integer number (8554240).

Almost surely, 2^91660599 is an apocalyptic number.

91660599 is a deficient number, since it is larger than the sum of its proper divisors (45207241).

91660599 is a wasteful number, since it uses less digits than its factorization.

91660599 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26867 (or 26861 counting only the distinct ones).

The product of its (nonzero) digits is 131220, while the sum is 45.

The square root of 91660599 is about 9573.9541987624. The cubic root of 91660599 is about 450.8799227363.

The spelling of 91660599 in words is "ninety-one million, six hundred sixty thousand, five hundred ninety-nine".