91125391212 has 144 divisors (see below), whose sum is σ = 237523104000. Its totient is φ = 29444688000.

The previous prime is 91125391187. The next prime is 91125391223. The reversal of 91125391212 is 21219352119.

91125391212 is a `hidden beast` number, since 9 + 112 + 539 + 1 + 2 + 1 + 2 = 666.

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 47 ways as a sum of consecutive naturals, for example, 60790039 + ... + 60791537.

It is an arithmetic number, because the mean of its divisors is an integer number (1649466000).

Almost surely, 2^91125391212 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 91125391212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118761552000).

91125391212 is an abundant number, since it is smaller than the sum of its proper divisors (146397712788).

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

91125391212 is a wasteful number, since it uses less digits than its factorization.

91125391212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1924 (or 1919 counting only the distinct ones).

The product of its digits is 9720, while the sum is 36.

The spelling of 91125391212 in words is "ninety-one billion, one hundred twenty-five million, three hundred ninety-one thousand, two hundred twelve".