20385388729 has 2 divisors, whose sum is σ = 20385388730. Its totient is φ = 20385388728.

The previous prime is 20385388703. The next prime is 20385388739. The reversal of 20385388729 is 92788358302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18891952704 + 1493436025 = 137448^2 + 38645^2 .

It is a cyclic number.

It is not a de Polignac number, because 20385388729 - 2⁹ = 20385388217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20385388729.

It is not a weakly prime, because it can be changed into another prime (20385388739) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10192694364 + 10192694365.

It is an arithmetic number, because the mean of its divisors is an integer number (10192694365).

Almost surely, 2^20385388729 is an apocalyptic number.

It is an amenable number.

20385388729 is a deficient number, since it is larger than the sum of its proper divisors (1).

20385388729 is an equidigital number, since it uses as much as digits as its factorization.

20385388729 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5806080, while the sum is 55.

The spelling of 20385388729 in words is "twenty billion, three hundred eighty-five million, three hundred eighty-eight thousand, seven hundred twenty-nine".