20389903 has 2 divisors, whose sum is σ = 20389904. Its totient is φ = 20389902.

The previous prime is 20389883. The next prime is 20389913. The reversal of 20389903 is 30998302.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20389903 - 2¹⁷ = 20258831 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20389913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10194951 + 10194952.

It is an arithmetic number, because the mean of its divisors is an integer number (10194952).

Almost surely, 2^20389903 is an apocalyptic number.

20389903 is a deficient number, since it is larger than the sum of its proper divisors (1).

20389903 is an equidigital number, since it uses as much as digits as its factorization.

20389903 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 20389903 is about 4515.5180212241. The cubic root of 20389903 is about 273.1943541268.

The spelling of 20389903 in words is "twenty million, three hundred eighty-nine thousand, nine hundred three".