91781344 has 48 divisors (see below), whose sum is σ = 185477040. Its totient is φ = 44692480.

The previous prime is 91781341. The next prime is 91781377. The reversal of 91781344 is 44318719.

91781344 = T₂₆₇ + T₂₆₈ + ... + T₈₂₈.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91781341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 326484 + ... + 326764.

It is an arithmetic number, because the mean of its divisors is an integer number (3864105).

Almost surely, 2^91781344 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91781344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92738520).

91781344 is an abundant number, since it is smaller than the sum of its proper divisors (93695696).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91781344 is a wasteful number, since it uses less digits than its factorization.

91781344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 523 (or 515 counting only the distinct ones).

The product of its digits is 24192, while the sum is 37.

The square root of 91781344 is about 9580.2580341033. The cubic root of 91781344 is about 451.0778180478.

The spelling of 91781344 in words is "ninety-one million, seven hundred eighty-one thousand, three hundred forty-four".