19891129727 has 12 divisors (see below), whose sum is σ = 23248335096. Its totient is φ = 16968727440.

The previous prime is 19891129723. The next prime is 19891129729. The reversal of 19891129727 is 72792119891.

It is not a de Polignac number, because 19891129727 - 2² = 19891129723 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19891129723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 951608 + ... + 972285.

It is an arithmetic number, because the mean of its divisors is an integer number (1937361258).

Almost surely, 2^19891129727 is an apocalyptic number.

19891129727 is a deficient number, since it is larger than the sum of its proper divisors (3357205369).

19891129727 is a wasteful number, since it uses less digits than its factorization.

19891129727 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1924118 (or 1924111 counting only the distinct ones).

The product of its digits is 1143072, while the sum is 56.

The spelling of 19891129727 in words is "nineteen billion, eight hundred ninety-one million, one hundred twenty-nine thousand, seven hundred twenty-seven".