99903809 has 2 divisors, whose sum is σ = 99903810. Its totient is φ = 99903808.

The previous prime is 99903799. The next prime is 99903821. The reversal of 99903809 is 90830999.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61277584 + 38626225 = 7828^2 + 6215^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-99903809 is a prime.

It is not a weakly prime, because it can be changed into another prime (99903109) 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, 49951904 + 49951905.

It is an arithmetic number, because the mean of its divisors is an integer number (49951905).

Almost surely, 2^99903809 is an apocalyptic number.

It is an amenable number.

99903809 is a deficient number, since it is larger than the sum of its proper divisors (1).

99903809 is an equidigital number, since it uses as much as digits as its factorization.

99903809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 157464, while the sum is 47.

The square root of 99903809 is about 9995.1892928548. The cubic root of 99903809 is about 464.0100092594.

The spelling of 99903809 in words is "ninety-nine million, nine hundred three thousand, eight hundred nine".