91181253312 has 448 divisors, whose sum is σ = 294948864000. Its totient is φ = 27497594880.

The previous prime is 91181253301. The next prime is 91181253341. The reversal of 91181253312 is 21335218119.

91181253312 is a `hidden beast` number, since 9 + 11 + 81 + 253 + 312 = 666.

It is a super-2 number, since 2×91181253312² (a number of 23 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 203076064 + ... + 203076512.

It is an arithmetic number, because the mean of its divisors is an integer number (658368000).

Almost surely, 2^91181253312 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 91181253312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (147474432000).

91181253312 is an abundant number, since it is smaller than the sum of its proper divisors (203767610688).

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

91181253312 is a wasteful number, since it uses less digits than its factorization.

91181253312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 741 (or 725 counting only the distinct ones).

The product of its digits is 12960, while the sum is 36.

The spelling of 91181253312 in words is "ninety-one billion, one hundred eighty-one million, two hundred fifty-three thousand, three hundred twelve".