9999911111 has 8 divisors (see below), whose sum is σ = 10281622848. Its totient is φ = 9720000000.

The previous prime is 9999911107. The next prime is 9999911113. The reversal of 9999911111 is 1111199999.

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

It is a cyclic number.

It is not a de Polignac number, because 9999911111 - 2² = 9999911107 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 9999911111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9999911113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is an upside-down number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 438890 + ... + 461111.

It is an arithmetic number, because the mean of its divisors is an integer number (1285202856).

Almost surely, 2^9999911111 is an apocalyptic number.

9999911111 is a deficient number, since it is larger than the sum of its proper divisors (281711737).

9999911111 is a wasteful number, since it uses less digits than its factorization.

9999911111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 900313.

The product of its digits is 59049, while the sum is 50.

The square root of 9999911111 is about 99999.5555540123. Note that the first 5 decimals coincide. The cubic root of 9999911111 is about 2154.4283064948.

It can be divided in two parts, 99999 and 11111, that multiplied together give a square (1111088889 = 33333²).

The spelling of 9999911111 in words is "nine billion, nine hundred ninety-nine million, nine hundred eleven thousand, one hundred eleven".