91540644 has 96 divisors (see below), whose sum is σ = 248070144. Its totient is φ = 26040960.

The previous prime is 91540639. The next prime is 91540649. The reversal of 91540644 is 44604519.

It is an interprime number because it is at equal distance from previous prime (91540639) and next prime (91540649).

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (91540649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 110817 + ... + 111639.

It is an arithmetic number, because the mean of its divisors is an integer number (2584064).

Almost surely, 2^91540644 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 91540644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124035072).

91540644 is an abundant number, since it is smaller than the sum of its proper divisors (156529500).

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

91540644 is a wasteful number, since it uses less digits than its factorization.

91540644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 897 (or 895 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 91540644 is about 9567.6874948966. The cubic root of 91540644 is about 450.6831500318.

The spelling of 91540644 in words is "ninety-one million, five hundred forty thousand, six hundred forty-four".