19889634447 has 12 divisors (see below), whose sum is σ = 28769438880. Its totient is φ = 13241310048.

The previous prime is 19889634439. The next prime is 19889634451. The reversal of 19889634447 is 74443698891.

It is not a de Polignac number, because 19889634447 - 2³ = 19889634439 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19889634407) 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 11 ways as a sum of consecutive naturals, for example, 1530358 + ... + 1543299.

It is an arithmetic number, because the mean of its divisors is an integer number (2397453240).

Almost surely, 2^19889634447 is an apocalyptic number.

19889634447 is a deficient number, since it is larger than the sum of its proper divisors (8879804433).

19889634447 is a wasteful number, since it uses less digits than its factorization.

19889634447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3074382 (or 3074379 counting only the distinct ones).

The product of its digits is 41803776, while the sum is 63.

The spelling of 19889634447 in words is "nineteen billion, eight hundred eighty-nine million, six hundred thirty-four thousand, four hundred forty-seven".