91223028 has 72 divisors (see below), whose sum is σ = 261424800. Its totient is φ = 26588736.

The previous prime is 91223023. The next prime is 91223051. The reversal of 91223028 is 82032219.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 91222992 and 91223010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91223021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3763 + ... + 14021.

It is an arithmetic number, because the mean of its divisors is an integer number (3630900).

Almost surely, 2^91223028 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 91223028, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130712400).

91223028 is an abundant number, since it is smaller than the sum of its proper divisors (170201772).

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

91223028 is a wasteful number, since it uses less digits than its factorization.

91223028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10301 (or 10296 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 91223028 is about 9551.0747039273. The cubic root of 91223028 is about 450.1613051353.

The spelling of 91223028 in words is "ninety-one million, two hundred twenty-three thousand, twenty-eight".