91391835656 has 64 divisors (see below), whose sum is σ = 195629230080. Its totient is φ = 39620764480.

The previous prime is 91391835653. The next prime is 91391835697. The reversal of 91391835656 is 65653819319.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (91391835653) 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, 637265 + ... + 767391.

It is an arithmetic number, because the mean of its divisors is an integer number (3056706720).

Almost surely, 2^91391835656 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 91391835656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97814615040).

91391835656 is an abundant number, since it is smaller than the sum of its proper divisors (104237394424).

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

91391835656 is a wasteful number, since it uses less digits than its factorization.

91391835656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130514 (or 130510 counting only the distinct ones).

The product of its digits is 5248800, while the sum is 56.

The spelling of 91391835656 in words is "ninety-one billion, three hundred ninety-one million, eight hundred thirty-five thousand, six hundred fifty-six".