91084728 has 96 divisors (see below), whose sum is σ = 268770960. Its totient is φ = 25643520.

The previous prime is 91084703. The next prime is 91084753. The reversal of 91084728 is 82748019.

It is an interprime number because it is at equal distance from previous prime (91084703) and next prime (91084753).

It is a super-3 number, since 3×91084728³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 85318 + ... + 86378.

Almost surely, 2^91084728 is an apocalyptic number.

91084728 is a gapful number since it is divisible by the number (98) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91084728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (134385480).

91084728 is an abundant number, since it is smaller than the sum of its proper divisors (177686232).

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

91084728 is a wasteful number, since it uses less digits than its factorization.

91084728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1157 (or 1146 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 39.

The square root of 91084728 is about 9543.8319348153. The cubic root of 91084728 is about 449.9336988739.

The spelling of 91084728 in words is "ninety-one million, eighty-four thousand, seven hundred twenty-eight".