9899409209 has 2 divisors, whose sum is σ = 9899409210. Its totient is φ = 9899409208.

The previous prime is 9899409197. The next prime is 9899409227. The reversal of 9899409209 is 9029049989.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9077325625 + 822083584 = 95275^2 + 28672^2 .

It is a cyclic number.

It is not a de Polignac number, because 9899409209 - 2⁴ = 9899409193 is a prime.

It is not a weakly prime, because it can be changed into another prime (9899409109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4949704604 + 4949704605.

It is an arithmetic number, because the mean of its divisors is an integer number (4949704605).

Almost surely, 2^9899409209 is an apocalyptic number.

It is an amenable number.

9899409209 is a deficient number, since it is larger than the sum of its proper divisors (1).

9899409209 is an equidigital number, since it uses as much as digits as its factorization.

9899409209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3779136, while the sum is 59.

The square root of 9899409209 is about 99495.7748298891. The cubic root of 9899409209 is about 2147.1864555879.

The spelling of 9899409209 in words is "nine billion, eight hundred ninety-nine million, four hundred nine thousand, two hundred nine".