91213851168 has 480 divisors, whose sum is σ = 307008092160. Its totient is φ = 26297187840.

The previous prime is 91213851151. The next prime is 91213851217. The reversal of 91213851168 is 86115831219.

91213851168 is a `hidden beast` number, since 9 + 121 + 3 + 8 + 511 + 6 + 8 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 240669603 + ... + 240669981.

It is an arithmetic number, because the mean of its divisors is an integer number (639600192).

Almost surely, 2^91213851168 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 91213851168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (153504046080).

91213851168 is an abundant number, since it is smaller than the sum of its proper divisors (215794240992).

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

91213851168 is a wasteful number, since it uses less digits than its factorization.

91213851168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 802 (or 785 counting only the distinct ones).

The product of its digits is 103680, while the sum is 45.

The spelling of 91213851168 in words is "ninety-one billion, two hundred thirteen million, eight hundred fifty-one thousand, one hundred sixty-eight".