91891395 has 32 divisors (see below), whose sum is σ = 165680640. Its totient is φ = 48313440.

The previous prime is 91891367. The next prime is 91891399. The reversal of 91891395 is 59319819.

It is a Cunningham number, because it is equal to 9586²-1.

It is not a de Polignac number, because 91891395 - 2⁸ = 91891139 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 91891395.

It is not an unprimeable number, because it can be changed into a prime (91891399) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4792 + ... + 14378.

It is an arithmetic number, because the mean of its divisors is an integer number (5177520).

Almost surely, 2^91891395 is an apocalyptic number.

91891395 is a deficient number, since it is larger than the sum of its proper divisors (73789245).

91891395 is a wasteful number, since it uses less digits than its factorization.

91891395 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9672 (or 9666 counting only the distinct ones).

The product of its digits is 87480, while the sum is 45.

The square root of 91891395 is about 9585.9999478406. Note that the first 4 decimals coincide. The cubic root of 91891395 is about 451.2580352720.

The spelling of 91891395 in words is "ninety-one million, eight hundred ninety-one thousand, three hundred ninety-five".