999820369 has 2 divisors, whose sum is σ = 999820370. Its totient is φ = 999820368.

The previous prime is 999820363. The next prime is 999820379. The reversal of 999820369 is 963028999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 975937600 + 23882769 = 31240^2 + 4887^2 .

It is a cyclic number.

It is not a de Polignac number, because 999820369 - 2¹¹ = 999818321 is a prime.

It is a super-2 number, since 2×999820369² = 1999281540534592322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (999820363) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499910184 + 499910185.

It is an arithmetic number, because the mean of its divisors is an integer number (499910185).

Almost surely, 2^999820369 is an apocalyptic number.

It is an amenable number.

999820369 is a deficient number, since it is larger than the sum of its proper divisors (1).

999820369 is an equidigital number, since it uses as much as digits as its factorization.

999820369 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1889568, while the sum is 55.

The square root of 999820369 is about 31619.9362586328. The cubic root of 999820369 is about 999.9401194144.

The spelling of 999820369 in words is "nine hundred ninety-nine million, eight hundred twenty thousand, three hundred sixty-nine".