91278528 has 84 divisors (see below), whose sum is σ = 265526520. Its totient is φ = 27653120.

The previous prime is 91278511. The next prime is 91278529. The reversal of 91278528 is 82587219.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 91278528.

It is not an unprimeable number, because it can be changed into a prime (91278529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21268 + ... + 25196.

It is an arithmetic number, because the mean of its divisors is an integer number (3161030).

Almost surely, 2^91278528 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 91278528, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (132763260).

91278528 is an abundant number, since it is smaller than the sum of its proper divisors (174247992).

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

91278528 is a wasteful number, since it uses less digits than its factorization.

91278528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3966 (or 3945 counting only the distinct ones).

The product of its digits is 80640, while the sum is 42.

The square root of 91278528 is about 9553.9796943473. The cubic root of 91278528 is about 450.2525791917.

It can be divided in two parts, 91278 and 528, that added together give a triangular number (91806 = T₄₂₈).

The spelling of 91278528 in words is "ninety-one million, two hundred seventy-eight thousand, five hundred twenty-eight".