91139566320 has 960 divisors, whose sum is σ = 388582272000. Its totient is φ = 18831605760.

The previous prime is 91139566313. The next prime is 91139566369. The reversal of 91139566320 is 2366593119.

91139566320 is a `hidden beast` number, since 9 + 1 + 1 + 3 + 9 + 5 + 6 + 632 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 58836906 + ... + 58838454.

It is an arithmetic number, because the mean of its divisors is an integer number (404773200).

Almost surely, 2^91139566320 is an apocalyptic number.

91139566320 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91139566320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (194291136000).

91139566320 is an abundant number, since it is smaller than the sum of its proper divisors (297442705680).

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

91139566320 is a wasteful number, since it uses less digits than its factorization.

91139566320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1638 (or 1629 counting only the distinct ones).

The product of its (nonzero) digits is 262440, while the sum is 45.

The spelling of 91139566320 in words is "ninety-one billion, one hundred thirty-nine million, five hundred sixty-six thousand, three hundred twenty".