91780919688960 has 864 divisors, whose sum is σ = 325631473876800. Its totient is φ = 23861152972800.

The previous prime is 91780919688947. The next prime is 91780919688977. The reversal of 91780919688960 is 6988691908719.

It is a self number, because there is not a number n which added to its sum of digits gives 91780919688960.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 70546440310 + ... + 70546441610.

It is an arithmetic number, because the mean of its divisors is an integer number (376888279950).

Almost surely, 2^{91780919688960} is an apocalyptic number.

91780919688960 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 91780919688960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (162815736938400).

91780919688960 is an abundant number, since it is smaller than the sum of its proper divisors (233850554187840).

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

91780919688960 is a wasteful number, since it uses less digits than its factorization.

91780919688960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2329 (or 2312 counting only the distinct ones).

The product of its (nonzero) digits is 846526464, while the sum is 81.

The spelling of 91780919688960 in words is "ninety-one trillion, seven hundred eighty billion, nine hundred nineteen million, six hundred eighty-eight thousand, nine hundred sixty".