999640026811 has 2 divisors, whose sum is σ = 999640026812. Its totient is φ = 999640026810.

The previous prime is 999640026767. The next prime is 999640026817. The reversal of 999640026811 is 118620046999.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 999640026811 - 2¹⁷ = 999639895739 is a prime.

It is not a weakly prime, because it can be changed into another prime (999640026817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499820013405 + 499820013406.

It is an arithmetic number, because the mean of its divisors is an integer number (499820013406).

Almost surely, 2^999640026811 is an apocalyptic number.

999640026811 is a deficient number, since it is larger than the sum of its proper divisors (1).

999640026811 is an equidigital number, since it uses as much as digits as its factorization.

999640026811 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1679616, while the sum is 55.

The spelling of 999640026811 in words is "nine hundred ninety-nine billion, six hundred forty million, twenty-six thousand, eight hundred eleven".