991068512 has 72 divisors (see below), whose sum is σ = 2343055680. Its totient is φ = 411022080.

The previous prime is 991068511. The next prime is 991068521. The reversal of 991068512 is 215860199.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 991068512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991068511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 38414 + ... + 58802.

It is an arithmetic number, because the mean of its divisors is an integer number (32542440).

Almost surely, 2^991068512 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 991068512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1171527840).

991068512 is an abundant number, since it is smaller than the sum of its proper divisors (1351987168).

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

991068512 is a wasteful number, since it uses less digits than its factorization.

991068512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20444 (or 20429 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 41.

The square root of 991068512 is about 31481.2406362901. The cubic root of 991068512 is about 997.0139295921.

The spelling of 991068512 in words is "nine hundred ninety-one million, sixty-eight thousand, five hundred twelve".