91028730 has 32 divisors (see below), whose sum is σ = 235275264. Its totient is φ = 22406976.

The previous prime is 91028713. The next prime is 91028731. The reversal of 91028730 is 3782019.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (91028731) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 116314 + ... + 117093.

It is an arithmetic number, because the mean of its divisors is an integer number (7352352).

Almost surely, 2^91028730 is an apocalyptic number.

91028730 is an abundant number, since it is smaller than the sum of its proper divisors (144246534).

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

91028730 is a wasteful number, since it uses less digits than its factorization.

91028730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233430.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 91028730 is about 9540.8977565007. The cubic root of 91028730 is about 449.8414750259.

The spelling of 91028730 in words is "ninety-one million, twenty-eight thousand, seven hundred thirty".