991099011 has 32 divisors (see below), whose sum is σ = 1564213248. Its totient is φ = 546446880.

The previous prime is 991099009. The next prime is 991099019. The reversal of 991099011 is 110990199.

991099011 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 991099011 - 2¹ = 991099009 is a prime.

It is not an unprimeable number, because it can be changed into a prime (991099019) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 63006 + ... + 77148.

It is an arithmetic number, because the mean of its divisors is an integer number (48881664).

Almost surely, 2^991099011 is an apocalyptic number.

991099011 is a deficient number, since it is larger than the sum of its proper divisors (573114237).

991099011 is a wasteful number, since it uses less digits than its factorization.

991099011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14271.

The product of its (nonzero) digits is 6561, while the sum is 39.

The square root of 991099011 is about 31481.7250321516. The cubic root of 991099011 is about 997.0241568083.

The spelling of 991099011 in words is "nine hundred ninety-one million, ninety-nine thousand, eleven".