999311111 has 2 divisors, whose sum is σ = 999311112. Its totient is φ = 999311110.

The previous prime is 999311077. The next prime is 999311113. The reversal of 999311111 is 111113999.

It is a strong prime.

It is an emirp because it is prime and its reverse (111113999) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-999311111 is a prime.

Together with 999311113, it forms a pair of twin primes.

It is a Chen prime.

999311111 is a modest number, since divided by 11111 gives 9993 as remainder.

It is a nialpdrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999311113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499655555 + 499655556.

It is an arithmetic number, because the mean of its divisors is an integer number (499655556).

Almost surely, 2^999311111 is an apocalyptic number.

999311111 is a deficient number, since it is larger than the sum of its proper divisors (1).

999311111 is an equidigital number, since it uses as much as digits as its factorization.

999311111 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2187, while the sum is 35.

The square root of 999311111 is about 31611.8824336672. The cubic root of 999311111 is about 999.7703175834.

The spelling of 999311111 in words is "nine hundred ninety-nine million, three hundred eleven thousand, one hundred eleven".