990000689 has 2 divisors, whose sum is σ = 990000690. Its totient is φ = 990000688.

The previous prime is 990000679. The next prime is 990000731. The reversal of 990000689 is 986000099.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 516198400 + 473802289 = 22720^2 + 21767^2 .

It is a cyclic number.

It is not a de Polignac number, because 990000689 - 2¹⁶ = 989935153 is a prime.

It is not a weakly prime, because it can be changed into another prime (990000619) 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, 495000344 + 495000345.

It is an arithmetic number, because the mean of its divisors is an integer number (495000345).

Almost surely, 2^990000689 is an apocalyptic number.

It is an amenable number.

990000689 is a deficient number, since it is larger than the sum of its proper divisors (1).

990000689 is an equidigital number, since it uses as much as digits as its factorization.

990000689 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34992, while the sum is 41.

The square root of 990000689 is about 31464.2763940314. The cubic root of 990000689 is about 996.6557246232.

The spelling of 990000689 in words is "nine hundred ninety million, six hundred eighty-nine", and thus it is an aban number.