991237812 has 48 divisors (see below), whose sum is σ = 2382604224. Its totient is φ = 320544000.

The previous prime is 991237811. The next prime is 991237813. The reversal of 991237812 is 218732199.

991237812 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (991237811) and next prime (991237813).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991237811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83487 + ... + 94617.

It is an arithmetic number, because the mean of its divisors is an integer number (49637588).

Almost surely, 2^991237812 is an apocalyptic number.

It is an amenable number.

991237812 is an abundant number, since it is smaller than the sum of its proper divisors (1391366412).

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

991237812 is a wasteful number, since it uses less digits than its factorization.

991237812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11360 (or 11358 counting only the distinct ones).

The product of its digits is 54432, while the sum is 42.

The square root of 991237812 is about 31483.9294243905. The cubic root of 991237812 is about 997.0706982364.

The spelling of 991237812 in words is "nine hundred ninety-one million, two hundred thirty-seven thousand, eight hundred twelve".