91771162056 has 128 divisors (see below), whose sum is σ = 291836160000. Its totient is φ = 26175410496.

The previous prime is 91771162013. The next prime is 91771162073. The reversal of 91771162056 is 65026117719.

91771162056 is a `hidden beast` number, since 9 + 1 + 7 + 7 + 11 + 620 + 5 + 6 = 666.

It is a super-2 number, since 2×91771162056² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 835845 + ... + 939243.

It is an arithmetic number, because the mean of its divisors is an integer number (2279970000).

Almost surely, 2^91771162056 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 91771162056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (145918080000).

91771162056 is an abundant number, since it is smaller than the sum of its proper divisors (200064997944).

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

91771162056 is a wasteful number, since it uses less digits than its factorization.

91771162056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104008 (or 103998 counting only the distinct ones).

The product of its (nonzero) digits is 158760, while the sum is 45.

The spelling of 91771162056 in words is "ninety-one billion, seven hundred seventy-one million, one hundred sixty-two thousand, fifty-six".