999640026841 has 2 divisors, whose sum is σ = 999640026842. Its totient is φ = 999640026840.

The previous prime is 999640026817. The next prime is 999640026883. The reversal of 999640026841 is 148620046999.

999640026841 = 706979² + 706980².

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 499820720400 + 499819306441 = 706980^2 + 706979^2 .

It is a cyclic number.

It is not a de Polignac number, because 999640026841 - 2¹¹ = 999640024793 is a prime.

It is not a weakly prime, because it can be changed into another prime (999640026811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499820013420 + 499820013421.

It is an arithmetic number, because the mean of its divisors is an integer number (499820013421).

Almost surely, 2^999640026841 is an apocalyptic number.

999640026841 is the 706980-th centered square number.

It is an amenable number.

999640026841 is a deficient number, since it is larger than the sum of its proper divisors (1).

999640026841 is an equidigital number, since it uses as much as digits as its factorization.

999640026841 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6718464, while the sum is 58.

The spelling of 999640026841 in words is "nine hundred ninety-nine billion, six hundred forty million, twenty-six thousand, eight hundred forty-one".