91000990080 has 1024 divisors, whose sum is σ = 432814233600. Its totient is φ = 17451417600.

The previous prime is 91000990061. The next prime is 91000990097. The reversal of 91000990080 is 8009900019.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 17294650 + ... + 17299910.

It is an arithmetic number, because the mean of its divisors is an integer number (422670150).

Almost surely, 2^91000990080 is an apocalyptic number.

91000990080 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 91000990080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (216407116800).

91000990080 is an abundant number, since it is smaller than the sum of its proper divisors (341813243520).

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

91000990080 is a wasteful number, since it uses less digits than its factorization.

91000990080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5320 (or 5302 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 36.

The spelling of 91000990080 in words is "ninety-one billion, nine hundred ninety thousand, eighty".