91681889280 has 352 divisors, whose sum is σ = 302697652224. Its totient is φ = 23670226944.

The previous prime is 91681889261. The next prime is 91681889329. The reversal of 91681889280 is 8298818619.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

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, 83880414 + ... + 83881506.

It is an arithmetic number, because the mean of its divisors is an integer number (859936512).

Almost surely, 2^91681889280 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 91681889280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151348826112).

91681889280 is an abundant number, since it is smaller than the sum of its proper divisors (211015762944).

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

91681889280 is a wasteful number, since it uses less digits than its factorization.

91681889280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1291 (or 1273 counting only the distinct ones).

The product of its (nonzero) digits is 3981312, while the sum is 60.

The spelling of 91681889280 in words is "ninety-one billion, six hundred eighty-one million, eight hundred eighty-nine thousand, two hundred eighty".