991012110111 has 12 divisors (see below), whose sum is σ = 1431659392488. Its totient is φ = 660583606704.

The previous prime is 991012110083. The next prime is 991012110133. The reversal of 991012110111 is 111011210199.

It is not a de Polignac number, because 991012110111 - 2⁵ = 991012110079 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991012115111) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7525545 + ... + 7656098.

It is an arithmetic number, because the mean of its divisors is an integer number (119304949374).

Almost surely, 2^991012110111 is an apocalyptic number.

991012110111 is a deficient number, since it is larger than the sum of its proper divisors (440647282377).

991012110111 is a wasteful number, since it uses less digits than its factorization.

991012110111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15188902 (or 15188899 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 27.

The spelling of 991012110111 in words is "nine hundred ninety-one billion, twelve million, one hundred ten thousand, one hundred eleven".