19938399125 has 8 divisors (see below), whose sum is σ = 24883122264. Its totient is φ = 15950719200.

The previous prime is 19938399083. The next prime is 19938399157. The reversal of 19938399125 is 52199383991.

It can be written as a sum of positive squares in 4 ways, for example, as 1418727556 + 18519671569 = 37666^2 + 136087^2 .

It is a de Polignac number, because none of the positive numbers 2^k-19938399125 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79753472 + ... + 79753721.

It is an arithmetic number, because the mean of its divisors is an integer number (3110390283).

Almost surely, 2^19938399125 is an apocalyptic number.

It is an amenable number.

19938399125 is a deficient number, since it is larger than the sum of its proper divisors (4944723139).

19938399125 is an equidigital number, since it uses as much as digits as its factorization.

19938399125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159507208 (or 159507198 counting only the distinct ones).

The product of its digits is 4723920, while the sum is 59.

The spelling of 19938399125 in words is "nineteen billion, nine hundred thirty-eight million, three hundred ninety-nine thousand, one hundred twenty-five".