91738443888 has 640 divisors, whose sum is σ = 343178035200. Its totient is φ = 22785297408.

The previous prime is 91738443887. The next prime is 91738443913. The reversal of 91738443888 is 88834483719.

91738443888 is a `hidden beast` number, since 9 + 173 + 84 + 4 + 388 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91738443883) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 196441831 + ... + 196442297.

It is an arithmetic number, because the mean of its divisors is an integer number (536215680).

Almost surely, 2^91738443888 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 91738443888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171589017600).

91738443888 is an abundant number, since it is smaller than the sum of its proper divisors (251439591312).

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

91738443888 is a wasteful number, since it uses less digits than its factorization.

91738443888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 786 (or 774 counting only the distinct ones).

The product of its digits is 37158912, while the sum is 63.

The spelling of 91738443888 in words is "ninety-one billion, seven hundred thirty-eight million, four hundred forty-three thousand, eight hundred eighty-eight".