990380609 has 2 divisors, whose sum is σ = 990380610. Its totient is φ = 990380608.

The previous prime is 990380581. The next prime is 990380623. The reversal of 990380609 is 906083099.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 957283600 + 33097009 = 30940^2 + 5753^2 .

It is a cyclic number.

It is not a de Polignac number, because 990380609 - 2²⁸ = 721945153 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 990380609.

It is not a weakly prime, because it can be changed into another prime (990380659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495190304 + 495190305.

It is an arithmetic number, because the mean of its divisors is an integer number (495190305).

Almost surely, 2^990380609 is an apocalyptic number.

It is an amenable number.

990380609 is a deficient number, since it is larger than the sum of its proper divisors (1).

990380609 is an equidigital number, since it uses as much as digits as its factorization.

990380609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 104976, while the sum is 44.

The square root of 990380609 is about 31470.3131379400. The cubic root of 990380609 is about 996.7831996243.

The spelling of 990380609 in words is "nine hundred ninety million, three hundred eighty thousand, six hundred nine".