19805556044 has 12 divisors (see below), whose sum is σ = 34693945104. Its totient is φ = 9893000304.

The previous prime is 19805556037. The next prime is 19805556047. The reversal of 19805556044 is 44065550891.

It is a self number, because there is not a number n which added to its sum of digits gives 19805556044.

It is not an unprimeable number, because it can be changed into a prime (19805556047) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2439872 + ... + 2447975.

It is an arithmetic number, because the mean of its divisors is an integer number (2891162092).

Almost surely, 2^19805556044 is an apocalyptic number.

It is an amenable number.

19805556044 is a deficient number, since it is larger than the sum of its proper divisors (14888389060).

19805556044 is a wasteful number, since it uses less digits than its factorization.

19805556044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4888864 (or 4888862 counting only the distinct ones).

The product of its (nonzero) digits is 864000, while the sum is 47.

The spelling of 19805556044 in words is "nineteen billion, eight hundred five million, five hundred fifty-six thousand, forty-four".