91077337728 has 192 divisors, whose sum is σ = 283488059400. Its totient is φ = 27900370944.

The previous prime is 91077337709. The next prime is 91077337739. The reversal of 91077337728 is 82773377019.

It can be written as a sum of positive squares in 4 ways, for example, as 80243025984 + 10834311744 = 283272^2 + 104088^2 .

It is a tau number, because it is divible by the number of its divisors (192).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3416226 + ... + 3442782.

Almost surely, 2^91077337728 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 91077337728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141744029700).

91077337728 is an abundant number, since it is smaller than the sum of its proper divisors (192410721672).

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

91077337728 is a wasteful number, since it uses less digits than its factorization.

91077337728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26819 (or 26804 counting only the distinct ones).

The product of its (nonzero) digits is 3111696, while the sum is 54.

The spelling of 91077337728 in words is "ninety-one billion, seventy-seven million, three hundred thirty-seven thousand, seven hundred twenty-eight".