20305189 has 2 divisors, whose sum is σ = 20305190. Its totient is φ = 20305188.

The previous prime is 20305171. The next prime is 20305199. The reversal of 20305189 is 98150302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16265089 + 4040100 = 4033^2 + 2010^2 .

It is a cyclic number.

It is not a de Polignac number, because 20305189 - 2¹¹ = 20303141 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20305199) 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, 10152594 + 10152595.

It is an arithmetic number, because the mean of its divisors is an integer number (10152595).

Almost surely, 2^20305189 is an apocalyptic number.

It is an amenable number.

20305189 is a deficient number, since it is larger than the sum of its proper divisors (1).

20305189 is an equidigital number, since it uses as much as digits as its factorization.

20305189 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 20305189 is about 4506.1279387075. The cubic root of 20305189 is about 272.8154817669.

The spelling of 20305189 in words is "twenty million, three hundred five thousand, one hundred eighty-nine".