91897449984 has 360 divisors, whose sum is σ = 284227717488. Its totient is φ = 28576972800.

The previous prime is 91897449949. The next prime is 91897449989. The reversal of 91897449984 is 48994479819.

91897449984 is a `hidden beast` number, since 9 + 1 + 8 + 97 + 449 + 98 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91897449989) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 201088284 + ... + 201088740.

Almost surely, 2^91897449984 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 91897449984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142113858744).

91897449984 is an abundant number, since it is smaller than the sum of its proper divisors (192330267504).

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

91897449984 is a wasteful number, since it uses less digits than its factorization.

91897449984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 666 (or 630 counting only the distinct ones).

The product of its digits is 188116992, while the sum is 72.

The spelling of 91897449984 in words is "ninety-one billion, eight hundred ninety-seven million, four hundred forty-nine thousand, nine hundred eighty-four".