91399741440 has 448 divisors, whose sum is σ = 340095352320. Its totient is φ = 20525875200.

The previous prime is 91399741427. The next prime is 91399741441. The reversal of 91399741440 is 4414799319.

It is a tau number, because it is divible by the number of its divisors (448).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91399741441) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 50748540 + ... + 50750340.

Almost surely, 2^91399741440 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 91399741440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (170047676160).

91399741440 is an abundant number, since it is smaller than the sum of its proper divisors (248695610880).

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

91399741440 is a wasteful number, since it uses less digits than its factorization.

91399741440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1901 (or 1877 counting only the distinct ones).

The product of its (nonzero) digits is 979776, while the sum is 51.

It can be divided in two parts, 9139 and 9741440, that added together give a palindrome (9750579).

The spelling of 91399741440 in words is "ninety-one billion, three hundred ninety-nine million, seven hundred forty-one thousand, four hundred forty".