991111131222 has 16 divisors (see below), whose sum is σ = 2068405839360. Its totient is φ = 316006447592.

The previous prime is 991111131211. The next prime is 991111131293. The reversal of 991111131222 is 222131111199.

991111131222 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3590982222 + ... + 3590982497.

It is an arithmetic number, because the mean of its divisors is an integer number (129275364960).

Almost surely, 2^991111131222 is an apocalyptic number.

991111131222 is an abundant number, since it is smaller than the sum of its proper divisors (1077294708138).

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

991111131222 is a wasteful number, since it uses less digits than its factorization.

991111131222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7181964747.

The product of its digits is 1944, while the sum is 33.

The spelling of 991111131222 in words is "nine hundred ninety-one billion, one hundred eleven million, one hundred thirty-one thousand, two hundred twenty-two".