991108911 has 8 divisors (see below), whose sum is σ = 1423130800. Its totient is φ = 609913152.

The previous prime is 991108883. The next prime is 991108961. The reversal of 991108911 is 119801199.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 991108911 - 2²⁹ = 454237999 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39), and also a Moran number because the ratio is a prime number: 25413049 = 991108911 / (9 + 9 + 1 + 1 + 0 + 8 + 9 + 1 + 1).

It is a self number, because there is not a number n which added to its sum of digits gives 991108911.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991108961) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12706486 + ... + 12706563.

It is an arithmetic number, because the mean of its divisors is an integer number (177891350).

Almost surely, 2^991108911 is an apocalyptic number.

991108911 is a deficient number, since it is larger than the sum of its proper divisors (432021889).

991108911 is a wasteful number, since it uses less digits than its factorization.

991108911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25413065.

The product of its (nonzero) digits is 5832, while the sum is 39.

The square root of 991108911 is about 31481.8822658366. The cubic root of 991108911 is about 997.0274765258.

The spelling of 991108911 in words is "nine hundred ninety-one million, one hundred eight thousand, nine hundred eleven".