91040385280 has 72 divisors (see below), whose sum is σ = 234844844472. Its totient is φ = 33614905344.

The previous prime is 91040385269. The next prime is 91040385349. The reversal of 91040385280 is 8258304019.

It can be written as a sum of positive squares in 4 ways, for example, as 21875593216 + 69164792064 = 147904^2 + 262992^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 2718949 + ... + 2752228.

It is an arithmetic number, because the mean of its divisors is an integer number (3261733951).

Almost surely, 2^91040385280 is an apocalyptic number.

It is an amenable number.

91040385280 is an abundant number, since it is smaller than the sum of its proper divisors (143804459192).

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

91040385280 is a wasteful number, since it uses less digits than its factorization.

91040385280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5471211 (or 5471197 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 40.

Adding to 91040385280 its reverse (8258304019), we get a palindrome (99298689299).

The spelling of 91040385280 in words is "ninety-one billion, forty million, three hundred eighty-five thousand, two hundred eighty".