19986444 has 36 divisors (see below), whose sum is σ = 52153920. Its totient is φ = 6446880.

The previous prime is 19986437. The next prime is 19986457. The reversal of 19986444 is 44468991.

It is a tau number, because it is divible by the number of its divisors (36).

It is a self number, because there is not a number n which added to its sum of digits gives 19986444.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7839 + ... + 10070.

It is an arithmetic number, because the mean of its divisors is an integer number (1448720).

Almost surely, 2^19986444 is an apocalyptic number.

It is an amenable number.

19986444 is an abundant number, since it is smaller than the sum of its proper divisors (32167476).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19986444 is a wasteful number, since it uses less digits than its factorization.

19986444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17950 (or 17945 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 19986444 is about 4470.6200912178. The cubic root of 19986444 is about 271.3804200563.

The spelling of 19986444 in words is "nineteen million, nine hundred eighty-six thousand, four hundred forty-four".