18839638745 has 4 divisors (see below), whose sum is σ = 22607566500. Its totient is φ = 15071710992.

The previous prime is 18839638723. The next prime is 18839638747. The reversal of 18839638745 is 54783693881.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3542154256 + 15297484489 = 59516^2 + 123683^2 .

It is a cyclic number.

It is not a de Polignac number, because 18839638745 - 2¹⁶ = 18839573209 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18839638747) 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 in 3 ways as a sum of consecutive naturals, for example, 1883963870 + ... + 1883963879.

It is an arithmetic number, because the mean of its divisors is an integer number (5651891625).

Almost surely, 2^18839638745 is an apocalyptic number.

It is an amenable number.

18839638745 is a deficient number, since it is larger than the sum of its proper divisors (3767927755).

18839638745 is an equidigital number, since it uses as much as digits as its factorization.

18839638745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3767927754.

The product of its digits is 34836480, while the sum is 62.

The spelling of 18839638745 in words is "eighteen billion, eight hundred thirty-nine million, six hundred thirty-eight thousand, seven hundred forty-five".