91475999 has 4 divisors (see below), whose sum is σ = 92004936. Its totient is φ = 90947064.

The previous prime is 91475987. The next prime is 91476001. The reversal of 91475999 is 99957419.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 91475999 - 2⁴ = 91475983 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 91475999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91475939) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 264209 + ... + 264554.

It is an arithmetic number, because the mean of its divisors is an integer number (23001234).

Almost surely, 2^91475999 is an apocalyptic number.

91475999 is a deficient number, since it is larger than the sum of its proper divisors (528937).

91475999 is a wasteful number, since it uses less digits than its factorization.

91475999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 528936.

The product of its digits is 918540, while the sum is 53.

The square root of 91475999 is about 9564.3086002073. The cubic root of 91475999 is about 450.5770358812.

The spelling of 91475999 in words is "ninety-one million, four hundred seventy-five thousand, nine hundred ninety-nine".