991100311 has 2 divisors, whose sum is σ = 991100312. Its totient is φ = 991100310.

The previous prime is 991100309. The next prime is 991100329. The reversal of 991100311 is 113001199.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 991100311 - 2¹ = 991100309 is a prime.

Together with 991100309, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (991100111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495550155 + 495550156.

It is an arithmetic number, because the mean of its divisors is an integer number (495550156).

Almost surely, 2^991100311 is an apocalyptic number.

991100311 is a deficient number, since it is larger than the sum of its proper divisors (1).

991100311 is an equidigital number, since it uses as much as digits as its factorization.

991100311 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 243, while the sum is 25.

The square root of 991100311 is about 31481.7456790439. The cubic root of 991100311 is about 997.0245927321.

The spelling of 991100311 in words is "nine hundred ninety-one million, one hundred thousand, three hundred eleven".