84902809 has 2 divisors, whose sum is σ = 84902810. Its totient is φ = 84902808.

The previous prime is 84902791. The next prime is 84902819. The reversal of 84902809 is 90820948.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47997184 + 36905625 = 6928^2 + 6075^2 .

It is a cyclic number.

It is not a de Polignac number, because 84902809 - 2¹⁷ = 84771737 is a prime.

It is not a weakly prime, because it can be changed into another prime (84902819) 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, 42451404 + 42451405.

It is an arithmetic number, because the mean of its divisors is an integer number (42451405).

Almost surely, 2^84902809 is an apocalyptic number.

It is an amenable number.

84902809 is a deficient number, since it is larger than the sum of its proper divisors (1).

84902809 is an equidigital number, since it uses as much as digits as its factorization.

84902809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 41472, while the sum is 40.

The square root of 84902809 is about 9214.2720276753. The cubic root of 84902809 is about 439.5153220197.

The spelling of 84902809 in words is "eighty-four million, nine hundred two thousand, eight hundred nine".