999997811 has 2 divisors, whose sum is σ = 999997812. Its totient is φ = 999997810.

The previous prime is 999997793. The next prime is 999997871. The reversal of 999997811 is 118799999.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 999997811 - 2²² = 995803507 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (999997871) 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, 499998905 + 499998906.

It is an arithmetic number, because the mean of its divisors is an integer number (499998906).

Almost surely, 2^999997811 is an apocalyptic number.

999997811 is a deficient number, since it is larger than the sum of its proper divisors (1).

999997811 is an equidigital number, since it uses as much as digits as its factorization.

999997811 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3306744, while the sum is 62.

The square root of 999997811 is about 31622.7419905359. The cubic root of 999997811 is about 999.9992703328. Note that the first 3 decimals are identical.

The spelling of 999997811 in words is "nine hundred ninety-nine million, nine hundred ninety-seven thousand, eight hundred eleven".