19998689399 has 16 divisors (see below), whose sum is σ = 21767054400. Its totient is φ = 18263529216.

The previous prime is 19998689327. The next prime is 19998689413. The reversal of 19998689399 is 99398689991.

It is a cyclic number.

It is not a de Polignac number, because 19998689399 - 2²⁸ = 19730253943 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19998689299) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1505117 + ... + 1518345.

It is an arithmetic number, because the mean of its divisors is an integer number (1360440900).

Almost surely, 2^19998689399 is an apocalyptic number.

19998689399 is a deficient number, since it is larger than the sum of its proper divisors (1768365001).

19998689399 is a wasteful number, since it uses less digits than its factorization.

19998689399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14474.

The product of its digits is 612220032, while the sum is 80.

The spelling of 19998689399 in words is "nineteen billion, nine hundred ninety-eight million, six hundred eighty-nine thousand, three hundred ninety-nine".