91311097680 has 960 divisors, whose sum is σ = 370632278016. Its totient is φ = 19888128000.

The previous prime is 91311097679. The next prime is 91311097687. The reversal of 91311097680 is 8679011319.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91311097687) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 546772957 + ... + 546773123.

Almost surely, 2^91311097680 is an apocalyptic number.

91311097680 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 91311097680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (185316139008).

91311097680 is an abundant number, since it is smaller than the sum of its proper divisors (279321180336).

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

91311097680 is a wasteful number, since it uses less digits than its factorization.

91311097680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 376 (or 367 counting only the distinct ones).

The product of its (nonzero) digits is 81648, while the sum is 45.

The spelling of 91311097680 in words is "ninety-one billion, three hundred eleven million, ninety-seven thousand, six hundred eighty".