91595991 has 8 divisors (see below), whose sum is σ = 123337584. Its totient is φ = 60459200.

The previous prime is 91595989. The next prime is 91596023. The reversal of 91595991 is 19959519.

It is a happy number.

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 91595991 - 2¹ = 91595989 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 91595991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91595921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 150846 + ... + 151451.

It is an arithmetic number, because the mean of its divisors is an integer number (15417198).

Almost surely, 2^91595991 is an apocalyptic number.

91595991 is a deficient number, since it is larger than the sum of its proper divisors (31741593).

91595991 is a wasteful number, since it uses less digits than its factorization.

91595991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302401.

The product of its digits is 164025, while the sum is 48.

The square root of 91595991 is about 9570.5794495422. The cubic root of 91595991 is about 450.7739619150.

The spelling of 91595991 in words is "ninety-one million, five hundred ninety-five thousand, nine hundred ninety-one".