91441891 has 4 divisors (see below), whose sum is σ = 91462000. Its totient is φ = 91421784.

The previous prime is 91441877. The next prime is 91441913. The reversal of 91441891 is 19814419.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19814419 = 103 ⋅192373.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91441891 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 91441891.

It is not an unprimeable number, because it can be changed into a prime (91441811) 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, 370 + ... + 13528.

It is an arithmetic number, because the mean of its divisors is an integer number (22865500).

Almost surely, 2^91441891 is an apocalyptic number.

91441891 is a deficient number, since it is larger than the sum of its proper divisors (20109).

91441891 is a wasteful number, since it uses less digits than its factorization.

91441891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20108.

The product of its digits is 10368, while the sum is 37.

The square root of 91441891 is about 9562.5253463716. The cubic root of 91441891 is about 450.5210277763.

The spelling of 91441891 in words is "ninety-one million, four hundred forty-one thousand, eight hundred ninety-one".