91091736 has 128 divisors (see below), whose sum is σ = 263736000. Its totient is φ = 29113344.

The previous prime is 91091731. The next prime is 91091747. The reversal of 91091736 is 63719019.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 91091736.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91091731) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 835650 + ... + 835758.

Almost surely, 2^91091736 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 91091736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (131868000).

91091736 is an abundant number, since it is smaller than the sum of its proper divisors (172644264).

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

91091736 is a wasteful number, since it uses less digits than its factorization.

91091736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250 (or 240 counting only the distinct ones).

The product of its (nonzero) digits is 10206, while the sum is 36.

The square root of 91091736 is about 9544.1990758785. The cubic root of 91091736 is about 449.9452377805.

The spelling of 91091736 in words is "ninety-one million, ninety-one thousand, seven hundred thirty-six".