91212912 has 240 divisors, whose sum is σ = 316646400. Its totient is φ = 25038720.

The previous prime is 91212911. The next prime is 91212923. The reversal of 91212912 is 21921219.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91212911) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 656139 + ... + 656277.

It is an arithmetic number, because the mean of its divisors is an integer number (1319360).

Almost surely, 2^91212912 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 91212912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (158323200).

91212912 is an abundant number, since it is smaller than the sum of its proper divisors (225433488).

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

91212912 is a wasteful number, since it uses less digits than its factorization.

91212912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201 (or 182 counting only the distinct ones).

The product of its digits is 648, while the sum is 27.

The square root of 91212912 is about 9550.5451153324. The cubic root of 91212912 is about 450.1446645998.

It can be divided in two parts, 912 and 12912, that added together give a cube (13824 = 24³).

The spelling of 91212912 in words is "ninety-one million, two hundred twelve thousand, nine hundred twelve".