991596911 has 2 divisors, whose sum is σ = 991596912. Its totient is φ = 991596910.

The previous prime is 991596889. The next prime is 991596919. The reversal of 991596911 is 119695199.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 991596911 - 2¹⁰ = 991595887 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 991596911.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (991596919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495798455 + 495798456.

It is an arithmetic number, because the mean of its divisors is an integer number (495798456).

Almost surely, 2^991596911 is an apocalyptic number.

991596911 is a deficient number, since it is larger than the sum of its proper divisors (1).

991596911 is an equidigital number, since it uses as much as digits as its factorization.

991596911 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 196830, while the sum is 50.

The square root of 991596911 is about 31489.6318015946. The cubic root of 991596911 is about 997.1910877326.

The spelling of 991596911 in words is "nine hundred ninety-one million, five hundred ninety-six thousand, nine hundred eleven".